If you plan on making your own Masks and painting your self , a couple of tips :
Paint colors in order , lightest first, followed by next lightest , and then darkest , no matter how many colors are used .
Lay masking tape onto a piece of glass or mirror ,draw on flames with a sharpie (a pencil also works well) then cut out shapes and apply to model . you can have a lot of fun with this technique . remember flames have no definite pattern so you will probably end up with your own personal style .
Remember to wait a couple of days between colors(for drying) and any mistakes can usually be covered up with following darker colors
After gaining a little experience you might want to try flame masks using Bare Metal Foil
(this is something I have been experimenting with as of late with pretty good results so far)