How to do a ariel? tips?

okay right now i'm working on my ariels ( and i mean the ones you do in gymnastics ) and i was wondering if anyone could share some tips on like how to get over the fear of doing one, how to get enough momentum to actually get off the ground and stuff like that:) thanks. oh and i already have my cartwheel roundoff and one handed cartwheel down and i have a soft floor to practice on:)