Don't ever shave! Just pluck ;) (using a tweezer)

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Whether or not you'll be wearing a sleeveless top/dress, do make it a habit to pluck :)
If you pluck often enough, you won't even have to shave!

Plucking is much better than shaving:-
(1) smoother
(2) armpit hair regrows at a much slower rate if you pluck
(2) hazard-free;) you needn't worry about accidentally shaving off your skin

What you need - a good pair of stainless steel tweezer

I started plucking ever since I had my first hair - at 15
so, I never had to shave
Some of my girlfriends used to shave, but ever since they started plucking, they LOVE it!
Do try plucking :)
If it hurts on your first attempt,..try using a bit of topical anesthesia

Where to get a good pair of tweezer:)
- Sasa Cosmetics - http://www.sasa.com/

Sasa.com offers round-the-clock access to the best beauty and health products –  worldwide shipping. Skincare, fragrance, makeup, slimming, haircare, nailcare, bath and body care, health and beauty supplements, as well as men's products