Depending on the medication there might be an "only time to take it" or it may not matter as much

Metformin can be taken anytime during the day - if taken before a meal it may reduce the stomach discomfort many experience - but try to make it a habit as in "always before breakfast or supper" so you don't forget

Other oral meds (except Sulfonylureas) - same time every day

Daily non-insulin Injectables - follow the Doctors orders
Weekly non-insulin Injectables - same time/same day every week

Sulfonylurea's - take exactly as prescribed eg. 30 minutes before a meal - and never take them and then skip the meal - they could kill you "today" if you do

Insulin whether Basil or Bolus - exactly as prescribed

Basil (long acting) typically before bed or first thing in the morning

Bolus (med/fast acting) - like the SU's - at whatever interval before a meal (typically 15 or 30 minutes) and again, don't skip the meal or you could invoke a Coma induced low leading to death

Mixed Insulin - the 75/25 or 70/30 stuff - exactly as prescribed

I take my meds after breakfast, and, evening, after supper; just saying