The L-shaped piece of plastic at the door end of the window fits into the door surround, making a J with the window when it's installed; if that makes sense.
Start the zip on the window, about and inch or 2, then curl the plastic edge of the window into the door surround channel; there should be fabric facing the front of the Jeep when it's in correctly.
Then finish the zip, and tuck the top of the window under the top flap of the top. Will be tightest at the door so tuck that under first and then seal the rest of the velcro.
Not just an X, a xXx, she's gonna get dirty!
'14 JKRX - Granite, 6-speed manual, soft-top, 430N, side air bags, Auto A/C. Mods: JWS8700Evo, Maximus-3 Stinger, Granite painted interior trim, 13" Antenna X, Rampage Locking Hood Latches, MC Grille Guard, Gibson Exhaust.