We use Present Simple with these TIME EXPRESSIONS (or KEY WORDS) 
  • every day/ morning/ week/ month/ year/... 
  • every other day
  • in the morning/ mornings/ evenings/...
  • on Mondays/ ... Sundays
  • at night
  • at seven o'clock/...
  • at weekends
  • in (the) winter/ spring/...
  • once/ twice or three times a day (a week/a month/...)
  • all the time
  • from time to time
These key words are usually used at the end of a sentence.
I read books every day.
But sometimes they can be used at the beginning of a sentence as well.
Once a week I visit my grandparents. (= I visit my grandparents once a week.)
  • always
  • nearly always
  • usually/ normally
  • regularly
  • often/ frequently
  • quite often
  • sometimes
  • not often
  • rarely
  • seldom
  • hardly ever
  • never
These key words are used 
  • after auxiliary verbs (be, have, etc.) - am sometimes late for school.
  • before other verbs.- sometimes help my parents.
Some key words (usually, sometimes etc.) can also go at the beginning or at the end of sentences if you want to emphasize them.
Sometimes I get up early. or I get up early sometimes.