How can my boyfriend stimulate me with fingers?

Probably the way you finger yourself. But first a few questions:

1. What do you mean by fingering? Clitoral stimulation or vaginal stimulation?
2. Are you a virgin?
3. Is hymen retention important to you?
4. Are there ant cultural or religious implications?
5. How old are you?
6. Where are you from?

1. Vaginal stimulation 2. Yes 3. No 4. No 5.15 6. London, UK

You didn't say how you finger yourself.
Once you are sufficiently lubricated and lying on your back, legs apart, he should insert his index finger (palm upwards), and feel for your g-spot which he should massage using a beckoning movement. When you are used to this, he should use two fingers. But he should not ignore your clitoris.
Try this to start with, and see how you get on, and I may be able to help more once you report back.