Slow progress is still faster than the person waiting for a perfect Monday.

Waiting has a hidden speed of zero. Somebody doing a small imperfect amount every few days is quietly ahead of somebody planning a flawless start, and the gap grows while the planning continues. Perfect conditions are also rare enough that building a plan around them is effectively choosing not to begin.

Begin the thing today in whatever bad form is available, fifteen minutes, wrong time of day, no proper setup. Keep the bar low enough that a tired version of you can clear it. You can improve the system later, once there is something to improve.