How to Paint a Galaxy: Step by Step for Beginners

A galaxy painting is the most universally requested beginner subject in the entire acrylic catalogue, and the reason is simple. It looks impossible. Swirling deep purples, glowing pinks, white starlight scattered across the canvas, the kind of cosmic drama that hangs in galleries and looks like it took weeks to paint. The good news is the technique is genuinely beginner-friendly, faster than almost any other tutorial in our library, and basically impossible to mess up because the universe itself is chaotic.

Here is the full step by step from the Paint Juicy team. The wet on wet blending move that creates the cosmic background, the dark-then-light layering trick, and the toothbrush splatter technique that makes the stars look real in about thirty seconds.

What you need before you start

The galaxy palette is small but specific. The colours are what make this work.

Acrylic paints in these colours: Titanium White, Mars Black, Phthalo Blue, Ultramarine Blue, Quinacridone Magenta, Dioxazine Purple (or any deep purple), and Cadmium Red. The deep purple is non-negotiable for a galaxy painting because it sits between the blues and the magentas to create the cosmic feel. Our guide on the best paint for paint and sip projects covers acrylics basics if you are starting from scratch.

A canvas in any orientation. Galaxies work brilliantly on square canvases, vertical for cosmic columns, or horizontal for sweeping nebulas. Pick whatever you have.

Brushes: a wide flat for the background blending, a medium round for the cosmic swirls, and a fine round for the larger stars. The secret weapon is an old toothbrush for splattering tiny stars, this is the move that makes everything click.

Plus paint palette, water, paper towels and an old shirt you do not love (galaxy painting is messy).

Step 1: Cover the canvas in solid black

Most galaxy tutorials skip this step and go straight to colour. That is a mistake. The black underpainting is what gives every other colour its depth. Cosmic colours look glowing and ethereal because they are layered over darkness, exactly like real space.

Load your wide flat brush with pure Mars Black and cover the entire canvas in solid opaque coverage. Use broad strokes in any direction, you are not aiming for texture here, just full coverage. Two coats may be needed depending on your canvas.

Let the black layer dry completely before moving on. About 10 minutes for acrylics.

Step 2: Plan your nebula shape

A galaxy painting needs a focal area where the cosmic colours will cluster. This is your nebula. Without a focal point the painting just looks like random colour smears across a black background.

Decide where your nebula will sit. Diagonal across the canvas (top-left to bottom-right or vice versa) is the most dramatic option and the easiest to compose. The nebula shape should be a soft elongated cloud, wider in the middle and tapering at the ends, roughly running across two thirds of the canvas.

You do not need to sketch this. Just commit to it mentally before you start adding colour.

Step 3: Build the nebula colours from dark to light

The galaxy colour order matters. Dark to light, cool to warm, always layered.

Load your medium round brush with Phthalo Blue and dab it across the entire planned nebula area in soft circular motions. Not a solid line, dabs and clusters, building up colour where the nebula will be brightest. Leave some black showing through the gaps. This is your darkest cosmic layer.

Without cleaning your brush, pick up Ultramarine Blue and add it on top of and around the Phthalo layer. The two blues mingle slightly creating depth.

Now switch to Dioxazine Purple. Add purple cloud dabs over the brightest areas of the nebula and slightly extending out into the edges. Purple is the bridge colour that connects blue to magenta.

Then Quinacridone Magenta. Add magenta dabs in the very brightest centre of the nebula, layered over the purple. The magenta should feel like the heart of the cosmic glow.

Finally a touch of Cadmium Red mixed with a small amount of magenta. Add tiny dabs of this warmer red right at the central peak of brightness, suggesting the hottest cosmic core.

The result should be a soft graduated nebula running from deep blue at the outer edges through purple in the middle to magenta and red at the brightest centre.

Step 4: Add white highlights to the brightest areas

This is the move that turns a colourful smear into an actual cosmic glow.

Load your medium round brush with pure Titanium White (clean brush first). Add small dabs of pure white over the very brightest centre of the nebula, where the magenta and red were strongest. The white will mix slightly with the magenta underneath, creating a soft pink glow at the heart of the cosmic cloud.

Keep the white localised to the brightest spots only. Adding white everywhere washes the painting out. Real nebulas have hot bright cores and cooler dim edges, the white belongs only at the centre.

Soften the edges of the white area by gently dabbing with a slightly damp clean brush, blending the white into the surrounding magenta. The result should look like the nebula is glowing from within rather than having a white dot painted on top.

Step 5: Splatter the stars (the magic move)

Pick up your old toothbrush. This is genuinely the best moment in the whole painting.

Squeeze a small amount of pure Titanium White onto your palette and add a tiny bit of water to thin it slightly, but not too much. You want the consistency of milk. Dip the bristles of the toothbrush into the white paint, just enough to load the bristles without dripping.

Hold the toothbrush about 15cm above the canvas, pointing the bristles toward the area you want to splatter. Run your thumb across the bristles in a quick scraping motion (the bristles flick away from you and back). Hundreds of tiny white droplets fly off the brush and land on the canvas as scattered stars.

Cover the entire canvas with splattered stars, focusing more density around the nebula and lighter scatter on the dark areas of empty space. Do two or three rounds of splattering for a layered effect, varying the distance from the canvas (closer for bigger stars, further for smaller ones).

If you accidentally hit a small area with too much splatter and one big white blob lands on the canvas, just touch the spot with your fingertip while wet to soften the shape into a star.

Stand back from the canvas. The painting suddenly looks like an actual photo of deep space.

Step 6: Add larger feature stars

Splatter stars are great for the overall starfield effect, but a galaxy painting needs a few prominent stars too. These are the stars that catch the eye and give the painting focal anchor points.

Take your fine round brush with pure Titanium White. Add 6 to 10 larger star dots scattered across the canvas. Vary the size and position. Some larger stars near the nebula edge, some smaller stars further out into the dark space.

For the biggest 2 or 3 stars, add a small four-pointed cross of light around each one using thin white strokes. A vertical line through the star, a horizontal line through the star, and the star will look like it is shining brightly with a corona effect. This is the kind of detail that real astrophotography captures and it makes your painting feel realistic.

Optional final touch. Add a few tiny coloured stars (a magenta dot here, a blue dot there) scattered through the dark areas. Real stars have different colours based on temperature and adding a few coloured ones reinforces the cosmic feel.

Common mistakes and how to fix them

The galaxy looks muddy and dark. You skipped the white highlight at the centre. Without that bright core, the colours all blend into a flat dark smear. Add pure white to the brightest centre and it will immediately glow.

The stars look like even dots in a grid. You painted them with a brush instead of splattering. Real starfields are random and varied. Use the toothbrush splatter technique even if it feels messy. The randomness is what makes it work.

The colours look chalky. Too much white mixed into your colours from the start. Let the colours stay rich and saturated, only adding white at the very brightest centre point. Chalky galaxies are a beginner trap.

Why we know this works

Galaxies are one of the most-requested subjects across our public sessions because they look impossible and feel achievable. The Paint Juicy team has taught this exact technique to thousands of beginners across Queensland, New South Wales and the Northern Territory. The toothbrush star trick is a fan favourite. Our FAQ on what to expect at a session walks through the format if you fancy joining us.