Make Players' skin/model update instantly

Simply type:

/cg_deferplayers 0

into the console, or add it to a .cfg file and exec it. Alternatively, you can find this option in the menu under Setup > Game Options > Defer Player Models: On/Off

There is a reason that this is not set like this normally; the game lags for a second when the new model is loaded and whenever a player connects, so I don't recommend using this if you are playing a match, but for normal play, the occasional small lag spike isn't really a problem.

To undo this, just set it back to 1.