How would I put in my LES after putting in my W-2? LES - Leave and earnings statement (Military "pay stub")

[SteamTrain]

You don't.

The W-2 is the proper form to input for your tax return.  The W-2 summarizes all your pay for the entire year in the proper tax format. 

Some people attempt to use their LES before they get their W-2, and later regret it because they find they entered the data wrong, and in the wrong place.  Never use an LES on your tax return....you use the W-2.