Lots of practice honestly. General tips though:

• Get paint on the brush then wick off some of the liquid on a paper towel so it doesn’t run. This might force you to do two layers minimum.
• Use the side/body of the brush instead of the tip and gently run it over the raised part at almost a 90° angle. similar to how you would do an edge highlight but with a deeper angle. This is the part that takes practice.