Well, I don’t have a vagina so I don’t know what the physical impulses feel like leading up to a clitoral orgasm, however as I understand it, there is an internal impulse to “back away” from seeing it through that accompanies it when masturbating, which most girls get past out of habit over time.
If it’s just you, and you don’t have a partner, I would say buy a run of the mill bullet vibe and hold it there so you can have that feeling and know what it’s like. That way you don’t have to concentrate on the motions but just on holding it there on your clit. You will cum, in all likelihood, within 10 minutes.
In time, you’ll probably be fine to do this yourself with just your fingers. It’s like anything else; the more you do it the more you can control. Some women can get themselves off on their way into work every day in a few minutes flat.
Us men aren’t so lucky. If I pulled my cock out on the freeway and stroked it I’d have a mess to clean up and would be paranoid. Needless to say, I still have done that a few times because sometimes I’m just so turned on, usually from short audio erotica stories, I’ve just lost all control and pulled my dick through the bottom of my shorts or pants and stroked, and dealt with the mess after. LOL. I can’t believe I just admitted that.