Its really simple as time management. Do 1 task per day/every other day for your startup (maybe 1-3 hours if you can spare) and at the end of 1 month, check you

Its really simple as time management. Do 1 task per day/every other day for your startup (maybe 1-3 hours if you can spare) and at the end of 1 month, check your progress. Rinse and Repeat until launch. Then do the same with marketing.