ok i will try and explain how to roll a L skin as best i can if not just roll 2 single skins and smoke them one after another.

ok take your first rizla and have it sticky side furthest away from you
Get the other rizla and place it at the top of the other rizla so that the sticky side is facing up and touching the top of the rizla ___| so its a 'L' shape' lick about a inch of the sticky bit of the rizla and stick the second rizla onto the first one so that it is secure, this will give you about an extra inch in length just roll like normal and lick the remaiing bit of the sticky sid of the 2nd rizla when sticking.

hope you understood this if not i done you a lil picture..you can also cut the rizla to your right where i have done a dotted line.