Ok so first you need to root your phone if you dont know how then go here first
Ok now after you have successfully rooted your phone flash cwm recovery from rom manager you will have to select lg sol
Then download the rom and the kernal from links below.
Then reboot into cwm and
Wipe dalvik cache
then go to mounts and storage and format system
Then you can flash cm7 then the kernal if you get any boot issues go back into cwm And wipe and reflash it should then work.
link to cm7 http://get.cm/?device=e730
link to kernal http://db.tt/lswDa3ZJ