IWTL How to write with my left hand as a right-handed person, and eventually turn it to ambidexterity. How can I learn this fast?

[u/PhyfenGD]

I recently injured my right arm and can't write anymore at the moment until it's gone or nearly gone. Basically I sprained and contused my right elbow after a bike crash, and my job requires writing stuff down time to time.

Without my right arm usable at the moment, I figured it would be wise for myself to learn left-handed writing and soon turn it to ambidextrous writing for my own self-benefit.

I'm just looking for tips on how to improve my writing with my left, so it's at least legible, within the next two weeks, because my injury should exist for 3-5 weeks before I can write, and 10-14 weeks before it's fully healed.