If you leave it in first . . . how is first even being shifted-into? Is it not already in 1st?

 

I leave it in first, but put it in nuetral and let the car warm up in the morning after I start it. Double clutching seems to work everytime for first and reverse though.

 

And I also pull it out of first because if I leave it in first, my very first movement will give a slight bump as I let the clutch out. I slowly let the pedal out, and it'll delay about ~1second before the clutch actually engages and I start moving.

 

....you live in california, there is no need to "warm" anything up

 

Besides which, modern cars only waste gas and increase emissions needlessly when let to sit & warm up. Just drive away. If the engine is really bouncing the car you might need new or filled roll stops (lower engine mounts).