Easy. When shaving in that area, it is best to take your time. It is a very sensitive place - alot more sensitive that legs/face/armpits - so it needs more care and attention.
NEVER DO A DRY SHAVE.
Obtain a nice fresh and new razor used specifically for this perpose, and change it every five shaves or so.
Always wet the area first, and use a sensitive foam or shaving cream (the one used for your face is fine) and slowly go with the hairs first, taking your time to get rid of it. Then go against the gain, so to speak. Carefully! Lather up with the cream if you plan on re shaving an area, so you're not risking your good work so far. Do not make a sudden movement, or you'll risk cutting yourself or you might get a rash, which would be awfully unpleasent.
Bare in mind, you do not need to remove it all at once. If this is your first time propperly shaving, try to narrow it down to nothing over a period of days.
Also, i recommed shaving every 3 - 4 days, so the hair and skin has to to repair itself. After shaving moisturise the area, it'll give your skin a chance to breathe! If you see red lumps, don't worry, they're not dangerous, and if any pimples occur, dont attempt to pop them. No good will come from it. If you have an allergic reaction on the other hand, stop using the cream you are, and move to another.
I hope this helps!
- Frankie xx
Hope this helps.