To make your Roblox profile look more colorful, you usually change your avatar’s skin/body colors in the Avatar editor. On the Roblox website, go to Avatar → Head & Body → Skin Tone , then pick a color; for separate colors on different body parts, use Advanced.

Mobile steps

On the Roblox app, open Avatar → Customize → Body → Skin , then choose the color you want. That changes your avatar’s look, which is the main “colorful profile” effect most players mean.

Extra colorful look

If you want your whole profile to feel more colorful, match your avatar colors with bright clothing, accessories, and hair. Some users also use profile/theme extensions or custom profile tools, but those are extra and not part of Roblox’s normal built-in avatar color settings.

Simple example

A quick setup is: bright hair, a neon shirt, and an avatar skin tone that contrasts with the outfit. That usually makes the profile stand out a lot more than just changing one color.

TL;DR: Open Avatar , change your Skin Tone or Body colors, and then add bright clothes/accessories for a more colorful Roblox profile.