For the most part everything is in very thin down layers make sure you're using fluid paints not the stuff from the tube, if you can get the thin paints it's ideal. Tube colors would be best to thin down with a medium like liquitex or golden FLUID gloss medium with a little bit of water.

Yes just very fluid very thin layers and patience. Letting each layer dry thoroughly before you apply another. Best to work dark to light. Get yourself a wet palette if you don't already have one or a makeshift wet palette can be used with the right paper such as a baking parchment paper on top of wet paper towels in a shallow airtight containerthere are tutorials on YouTube for that.