Bi girl here. My personal favorite and what has gotten the most positive reviews (everyone has preferences, listen to those if given, if not this is my go to)

Some thrusting. Don't take your fingers all the way out, out really much out though. Instead you want your elbow against your hip and thrust that into her with however much force she prefers. You're not actually moving the depth of your fingers much (personally I've always found too much depth movement fingering dries me out and scrapes me), but the power behind the thrust allows you to use your palm for clit fun and also it feels really fucking good.

So then when you have "thrusted" in, you use your fingers in either a come here or circle, depending on her preference between the two. You get into a rhythm with your thrusts and finger movements.

Once you get the hang of synchronizing the movements you get to really have fun. From this you can get some clit action with the palm or a vibrator. That shit can be synched up with the thrusts pretty easily as well. You will get the hang of this shit and realize you are using one hand and only the lower half of your body.

You know what that means? You can actually be kissing, fondling, etc her at the same time. This, for me, is something often neglected in fingering but is my favorite part.