Tomorrow is not a feasible option for entrepreneurs. Never keep anything aside for tomorrow, if you think it really important. However, to reap the success as a startup Entrepreneur you must develop a bunch of positive habits/philosophy. Let's check some of them.
Screw it, let's do it now: If not now then never. If you need to call someone, pick the phone, dial the number, talk and finish. No second thought. You can better learn this strategy or habit from Richard Branson. If you want to feel more motivated I would suggest to read Branson's Screw it, let's do it.