Depilatories are not save for genital use.
Yes you should trim before shaving.
The more you shave the faster your skin will adapt - daily or every other day is best.
Use a high-end multi-blade razor like the Gillette fusion
I use hair conditioner as a shave cream - it's just like coochy-cream but cheaper
Consider an after shave specifically made for sensitive skin - you can find them on EF
Also consider using an exfoliating scrub before shaving to prevent ingrown hairs.
It sounds like a lot - but my wife and I are hooked on the smooth-on-smooth aspect of sex. It makes both of us far more sensitive to all types of stimulation - including oral.