List everything you want to accomplish, rank it by impact, and commit to only the top 5 — everything else waits until those are done.
Run every task on your list through this filter, then work strictly in order — all your A's before any B, all your B's before any C, and so on.
Split your to-dos into three groups: To Do (everything that needs to get done soon), Doing (what you're actively working on), and Done (already finished).