There's that word which always seems to get us in trouble "assumed"...

The gyro's function is to keep the tail boom where you put it, not keep the heli hovering.

Try different heli's on the sim, some are much easier to fly than others. The high performance ones capable of 3D are really touchy and you won't get far trying to learn with them. Try the one listed as a trainer, it has the training gear attached and it's much easier to hover than anything else I've played with on the sim.

Calibrate your controller with the trims centered. What I like to do for trimming is to gradually increase the power until it starts to just slightly lift, note what direction it tends to go and trim to offset that tendency. Once you get it to lift pretty straight, and that's immediately off the ground, the trims are probably as close as you'll get until your flying skills improve.

Hovering is one of the toughest new skills to learn so some recommend lifting it and learning to fly it around keeping the tailboom behind you and accepting the crashes until you get familiar with the stick movements. Most people I've talked to about it say you should learn to hover with it pointing away from you, I prefer it facing me but the stick movements are reversed for left/right movement as they are with a fixed wing model.

There is a tutorial a lot of people refer to as being very good, but I can't find the link to it right now as I've not tried the tutorial. Perhaps someone here can direct you to it or offer other better input as I'm not an expert on heli flying by any means...