I purchased my grandson a Bachmann set for Christmas. I also included a remote switch set, which we did not install. He wanted me to help him install the switch set last week but he had thrown away all of the instructions. He has the basic power controller that has two accessory connections but we have no idea how to connect the switches. Any help would be appreciated. Also would like recommendations on a better controller to control multiple accessories.  Thanks for your help.

This will give you instructions for installing the controller for the switch/turnout.
http://www.bachmanntrains.com/home-usa/dwg/dwgs/HO__6_Turnouts_Instructions.pdf

Other controllers for accessories will depend on the specific accessory, ie. does it require an on/off switch or a momentary switch.

Thanks for the diagram. That makes it a lot easier.