If you can't seem to close the snap straps on your Beach LT, first make sure that the kayak flap with the curved edge isn't pushing on your strap, causing it to shorten (see photo above for reference).
You don't want the strap to reach in a diagonal direction; rather, you want it to reach straight across. If you can align the flaps so that the snap-on button is directly across from the strap, then pull straight up and across, the strap should reach. We recommend fastening the middle snap first, before attempting the other two.
If you are still struggling to close the snap straps, please watch this video. Prepping that first fold will really help - also, please note that your kayak will be stiff during the first few assemblies. It does get easier over time, as the boat "settles" into its folds.