I'm a man and I shower everyday twice per day as in once in the morning and once in the evening before bed after I get home from work.
I could not go any longer than 1 day without showering however it's okay to shower every other day if you want too.
But when you shower everyday you make sure you remove body odor and help your body smell much better.
You'll also feel much better when you should everyday at least once per day.
But it's okay to shower every other day if you want too unless you're sweating a lot especially after exercising, working out or just being out in the hot weather.
I feel icky if I don't shower at least once everyday and I have had to go a week before without showering when I had no water due to a plumbing problem and that was awful.