>>67012113No brand recommendations (except /against/ Axe; overpriced fragrance won't get you laid despite the marketing BS), I've used various brands without much issue, just put a generous amount on every morning, enough to cover the entire pit, using a little bit too much is better than using a little bit too little. Primary problem is occasionally not covering enough of the pits.
HOWEVER, I've read that putting it on at night might be better, since it takes time for the antiperspirant to take effect. I haven't tested this.
If you're a light sweater, or you shower daily, you don't necessarily need antiperspirant. Lots of people just use ordinary deodorant. I use antiperspirant because I could never stand my armpits being damp.
Note that even with antiperspirant, you may still acquire BO if you push it too long. Also antiperspirant only works in the underarm region (at least for me), it won't keep your groin or behind the ears from stinking (clothing will usually block the former, and afaik the latter is due to sebum, not sweat.)
Regardless, being legitimately clean is good for your mental health so I recommend showering daily if you can manage it.