There was a fellow that frequented our local hobby dealer that had a similar problem with another plane, that is, it was too heavy. His solution? Cut about 6" off each wing tip to lower the weight.

(OK, it's not the 1st of April...)

Seriously, try to use a long paved runway and keep it on the ground as long as you can. Don't try to force it off the ground. If it does get airborne be very gentle and practice landings up in the air. No violent maneuvers and keep the speed up during final approach.

If it doesn't look like it's ever gonna leave the ground, find a local restaurant that wants to hang it up for decoration and save the engine and radio stuff for another plane