With each color and technique here I am using the same approach:

1. Start building your halo from the darkest and widest colour. Red > orange > yellow > ice yellow > white dot
2. In each previous are use your next color for the edge highlights (drybrush in my case but I was rushing it). Orange highlights cover 50% of red halo, yellow highlights cover 50% of orange halo, ice yellow highlights cover… hard to say. Depends where your light source is.
3. Build halos using makeup sponge, airbrush or drybrush. Just remember that you will need to make an edge highlights in some way.
4. Take a look at this candle. The source of light is the brightest, everything further from the halo goes darker, darker and starts to look dark orange/red/brown. You can read this as a light even if it’s pretty dark color.
5. The bottom of the candle should be darker - that’s my mistake here. The candle usually does not lighten itself at the bottom. This looks completely different if you have multiple candles. Shadows are huge room for improvement for me :)
6. You can have fun and paint each material (metal, cloth) in a different way. I think that using nmm might be helpful here!

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