It is better to spend your days, focusing on your days. And by 'days' I mean … Today!
There is absolutely no point, no sense and no logic in thinking about tomorrow, unless you are doing so in order to make a decision.
'Tomorrow thoughts' should only occur (simultaneously) with decision making. Any thinking of tomorrow is a waste of time, because it is what you do right now, today, that defines tomorrow.
Even if you are planning ahead, arranging goals or thinking about the future, you have to keep in mind the fact that you can't execute your plans, achieve your goals or change your future, without first making a decision today.
Your decisions define everything that you do and everything that happens in your life. Your decisions are the keys that open the doors (good or bad) so you have to be aware of how you make them, and be responsible for them.
The more you do that, the more you influence your future!