I rarely do pantos but when i do I go end to end and don't stop at borders.
Here is a good trick. Go to wallmart and buy yourself a clear vinyl shower curtain liner. Cut it down to the width of your LA table (it won't be long enough you will have to cut two pieces. One curtain will be ample for a 12 ft table. Tape the vinyl to your table at the top ONLY so it is like a flap. When you place your panto lift your vinyl flap and put your panto under then bring the clear vinyl over your panto. Now you have a clear vinyl protector for your pantos. You can put a piece of painters tape down over the vinyl where you are to stop and and start and it helps keep your panto clean and protected.