All the things we really like to do are either illegal, immoral, fattening or carcinogenic (cancer causing).

(with due apologies to Alexander Woollcott)

Nevertheless here is an incomplete list of things to do to remain healthy, try following some/all of them

Drink lots of water

Laugh a lot

Live close to nature

Listen more, speak less

Do not smoke

Drink in moderation

Exercise regularly

Spend time outdoors

Meditate

Keep smiling

Listen to music

Pursue your passions

Sit doing nothing now and then

Have a mission in life

Take lots of fruits and vegetables