I've found that the key is to have a really good men's razor and a bottle of unscented/dyed hair conditioner like Suave (it's super cheap). Apply the conditioner five minutes before you get ready to shave, just rub it in and then do other stuff in the shower while you're waiting. Hold the skin taught and shave against the grain if the hair is longer than a 1/4 of an inch and with the grain if it's shorter. If you go with the grain, reapply the conditioner and then shave against the grain while pulling the skin taught and go in smooth, even strokes.

Ever since I started shaving this way, I haven't had a problem with ingrown hairs or red bumps. A soothing shea or cocoa butter lotion to smooth over the skin after the fact always helps too!

I recently got an epilator & it's the best thing ever. I'm telling everyone to get one. Only hair removal thingy I've ever actually been happy with & able to de-fuzz my whole pubic area with without worrying about cuts or whatnot. (Just make sure to trim first so it doesn't try to suck you in by the hair. Hehe. - Read the directions. )

The one I use is basically like 40 little pairs of tweezers on a rotating shaft. Link I know that may sound painful, but it's really not bad. Not as bad as waxing, but you have the same advantage of hair growing back less thick & sharp. I've only gotten a couple ingrown hairs since I started using it & they weren't nasty ones. Just had to grab them with tweezers & all was fine.

And they're $35 so no huge investment if it's not the thing for you.

I never had problems with bumps and ingrown hairs until I started waxing, and then it was horrible for almost a year. Now it's almost back to normal. Almost.

For me, there's a series of things i find super important. I always use a fresh sharp flexible razor. I always exfoliate the areas I shave regularly, and areas prone to ingrown hairs I exfoliate with a gentle facial scrub with a low dose of salicylic acid in it. While shaving, I like prepping with aveeno oatmeal bars which are super moisturizing and lovely. I use them when shaving my legs too. After the shave, I use a cetaphil antibacterial bar and then a gentle moisturizer when I get out.

The whole series helps make sure your skin is clean and soft and the exfoliation helps prevent the hair from getting trapped just under the skin. The salicylic acid also helps draw out any infection there might be plus any hairs that would be otherwise tempted to curl back under.

Hope that helps!