As far the act of landing goes......
While balancing..... stand in dish/hollow/scoop shape that has your knees and hips slightly bent with your heels 1-2 inches off the floor. Tension all the muscles it takes to hold this position. Remain in this position and tension while a team mate holds you by your shoulders and tips you forward and backward. The person helping you will have to change from standing in front to standing behind you. You only need to be tipped enough that you can feel the effort it takes to hold this position and remember what you want to open to as you finish the skill. Add to your work by standing in that position and resist a team mates efforts to straighten your legs, or hips
Another thing is to think of what"s going through your head as you prepare fr the finish of the skill. If you asked me, and I guess you are, I'd say you're searching or reaching for the mat because you're not 100% certain where you and the mat are relative to each other. Sure you want to "find" the mat, but you don't do that by reaching down, or out, with your feet/legs.
Make sure you rotate while opening......
The best way to find the mat it is to trust that gravity will always get you down to it, and you're never going to go off to the side or out too far to miss it. That will free your mind to do something that will really help, mainly to keep a rotation frame of mind as you open to the landing position at the end of the skill. That means keeping your shoulders reaching forward and down with the same energy you used to start the rotation on the skill. So it's kinda like staying tucked from your belly button to your forehead while opening your hips and knees to the landing position/posture/shape.
Work it like this onto a stack of safety mats until you feel ready to take the top mat off and replace it with a four inch landing mat, and when ready you should replace the four inch mat with a one inch mat. So if you start with three 8 inch mats. Continue to take mats away until you get to a competition mat set.
Work hard and learn easy.