Could you tell me what's the best way to numb pain while getting a tattoo?

I'd urge you not to: Most areas, especially those far away from bone, will not be that uncomfortable. There's are a variety of topical creams with Lidocaine or other 'caine products, ask your artist whether these are right. Acetaminophen is a good choice for an oral analgesic as it doesn't interfere with platelet function. You may find the sensations, even if not pleasant, make this meaningful experience even richer.