A Stoic answers
What would a Stoic do about procrastination?
A Stoic treats procrastination as a failure to remember two things: that time is the one thing you cannot get back, and that you will never feel fully ready. The cure is not motivation but a decision. You do the work because it is yours to do and because this hour is real, while the future you are bargaining with may never come. Start before you feel like it; the feeling follows the action, not the other way around.
The principleMemento mori. We act as if we have unlimited time, and so we waste it. Knowing the day is finite is what makes it worth using well.
What the philosophers say

Marcus told himself at dawn that he was rising to do the work of a human being. When you do not want to get up, ask: was I made for this, to lie warm under the blankets, or to act? The work is the point of you.

Seneca opens his letters by attacking delay itself: we are not given a short life, he says, but we make it short by squandering it. Hold every hour as if it were the last of a small and precious store.

Epictetus would ask how long you mean to wait before you demand the best of yourself. You are no longer a child. Decide who you want to be, then do the thing that person does, today.
Try this
- Name the smallest first action and do only that. Starting is the whole battle.
- Stop waiting to feel ready; the feeling arrives after you begin, not before.
- Remember the day is finite. Ask: if my time is short, is this really what I want to be avoiding?
- Tie the task to who you want to be, not to whether you feel like it.
Questions
What is the Stoic cure for procrastination?
Decide rather than wait for motivation: do the smallest next action now, because the feeling of readiness follows action, and because your time is finite.
Which Stoic text is best on wasting time?
Seneca's essay On the Shortness of Life, and the opening of his Letters to Lucilius, both argue that we lose life not because it is short but because we squander it.
Ask them yourself
Put your own situation to Marcus, Seneca or Epictetus and hear them answer in their own words.
Talk to a Stoic