Work out when you feel less tired throughout the day , if you’re not a morning person don’t work out in the morning. If you sleep early don’t go to the gym at 9 pm. Know your body time. Also don’t feel bad for skipping gym sometimes, it’s ok, don’t feel like a failure , even if you fail to go once or twice, it’s alright. What matters is always trying even if it’s twice a month. As you get stronger you’ll naturally have more motivation and energy and you’ll feel weird when you don’t work out. That’s my experience