If you run the battery in your RC, there's really no need to discharge it on the charger. You should have a manual, just go to program select for NiMh and then NiMh Main, set the amps you want and press and hold start/enter to start the charging. The defaults will take care of the rest until you're ready to understand those and where to find/change them.
If you had said what size/capacity (mah) pac you have, we could suggest a charge rate.....