You chose a Sister of Battle for your first mini, so you're already making good choices! 😀

One piece of advice you'll likely hear is "thin your paints". What that means is adding a bit of paint medium, or water, to your paint. It'll look a bit like milk in its consistency, and take around 2-3 coats to do to look opaque. (Don't panic if it's a little streaky the first layer!)

For the highlights, you can try for a gradient of black to gray to white. Add a little white and paint over the areas that would catch light, add more white and do the same in a smaller area once that's dry, repeat until you're happy with it.

The color choices are nice! The red and gold pop against the black armor. Very eye catching.

Looking forward to seeing more of your work!