Test the water with one toe before the cannonball. Brave people still check the depth.

Checking the depth is not the opposite of jumping, it is how experienced people jump. A small version first gives you real information cheaply: whether you like it, whether the thing works, who else turns out to be involved. Most disasters come from skipping that step rather than from insufficient boldness.

Before a big commitment, find the one-week version. One class before the degree, one shift before the job, one trip before the move. Then decide from something you have actually felt instead of something you imagined.