Using a facecloth with warm water before shaving helps reduce razor bumps.
Soften your hair by dampening your face with warm water before shaving. This makes your shave more even throughout and decreases the likelihood of angular cuts, which cause razor bumps. The best way to soften facial hair is to lay a warm, wet towel over your beard and mustache area for approximately five minutes before shaving. This tactic ensures the smoothest possible shave, prevents new razor bumps from forming, and prevents against further irritation of any razor bumps you have.
Don't ever shave against the grain.
Shave properly in order to avoid new razor bumps, and to prevent cutting and scarring of existing razor bumps. Apply shaving cream to your face and allow it to soak into your skin and facial hair for two minutes before shaving. When ready to shave, be sure not to cut the hair against the grain and avoid shaving the same patch more than once. Shaving an area multiple times can cause irritation and will likely result in new razor bumps or exacerbation of existing razor bumps.
If changing your shaving tactics doesn't rid you of razor bumps, try a specialty product.
If these things don't work, consider a specialty product like Tea Tree Oil (thebodyshop-usa.com/tea-tree/prod170278), Soothing Plant After Shave Gel by Living Nature (livingnature.com/catalog/main.cfm?t=p&r=vw&pid=531&cid=1881), or Men's Stock North Woods After Shave Balm (aubrey-organics.com/ProductInfo.aspx?productid=4007) to your shaving regimen.