The rotary knobs are the compression changeover valves. Screw clockwise until they seat to put the engine in high compression (for starting). Once the engine's running, they can be spun out until they stop, now the engine is in low compression. This is the preferred operating mode.
The buttons on the other side are the decompressors, one per cylinder. Their purpose is to hold the exhaust valve open (pulled out), to give you a chance of spinning the engine, by hand, sufficiently fast to start it. The tricky part, in your situation, is going to be reaching around the front wheel to hit the decompressor, preferably without getting tangled in the starting handle and before you lose too much momentum! My old JP4 had a long rod on it, which ran past all the decompressors to the front; having worked up a sweat turning the engine, you could engage all the decompression buttons at once.... at which point, you just had to hope it fired on the first cylinder, or you were screwed!
So, the starting procedure would be: Pull both decompression buttons out. Turn the compression changeover knobs to high compression. Ensure fuel is switched on. Crank on the starting handle as hard as you can.... get a friend to push one of the decompressor buttons in. Keep cranking! When it fires and starts to run by itself, push the other decompressor in. It should pick up and run on both cyls. Once it's been running for a few seconds, unscrew one of the decompression knobs until it stops huffing and runs on two cyls again. Repeat with the other one. Job's a good 'un! Make sure you video it and post on youtube.... a) People love to see/hear old Listers run. b) Comedy gold potential