Umm... that's a pretty obvious question. No. Guys should not wear bikinis. The closest thing to a bikini that guys can get is a speedo, and those should only be worn when competing for swim. Otherwise it's just gross.
Edit: It depends on where the guy is and what the styles are there, and how in-shape he is. For example, in Europe guys of all ages wear bikinis (I'm not saying they look good in them, but they do wear them) and in the USA really, seriously FIT guys in Miami often wear bikinis.
As a rule: look at what the men of your age and body type are wearing in the place you will be. If they're wearing bikinis...go for it. If they're wearing board shorts -- do NOT wear the bikini!! When in doubt, look up the Undergear catalogue online...and if you don't look like those models, DON'T wear what they're wearing.
Men should wear speedos and woman should wear bikinis and bras
It attracts many men, so more people can come.
They wear bikinis, bras, and thongs.
No, jennette mccurdy does not wear bikinis because she does not like showing her belly. If she was swimming she would wear a vest and long legging's.
they will wear bikinis
they wear shoes.
they wear fur bikinis made from polar bears
yes
bikinis and booty shorts
it depends on the gender.
They wore bikinis
Men have many styles of underwear. They include bikinis, boxer briefs, briefs, boxers, and long johns. The style you choose to wear depends on the amount of support or freedom you prefer.