I use a chicken stick, and more often than not my engine starts backwards. I have a throttle kill switch on my Tx, and tapping that will make the engine 'cough' and it will start itself running the right direction. Haven't tried playing with the low end yet, so maybe that might be an answer. What is happening is 'hydro lock' where there is a bunch of fuel in the cylinder and not enough energy to compress it to ignition, so it stops the piston abruptly, and the reaction forces it to spin the opposite way. Another thing to try is a 'running start' where you turn the prop clockwise until just before compression, then flip the prop, giving yourself some resistance free movement to build up momentum into the compression stroke.

If you're using a starter, feel free to push the starter on the cone and hold it there, firmly, until you know the engine is running well.