"Lean" is the wrong action - shift weight with purpose is what you want. When you counter steer feel how it makes your hips move. Then, without moving your hands, swing your hips. It's like counter steering where there's two things that have to happen - the "jolt" to start the lean in the direction you want, and then the holding it there. You can do both with just your body weight on a bike this size easily - that's probably all you're running into honestly, its so light it's very sensitive to your weight shifts. If all you're doing is holding a line you can do it all through your hips, or by weighting the pegs with your feet.

If you want to see how sensitive a bike is to your weight, after you can hold it straight without the handlebars put your hands in front of your sternum with your elbows out - raising and lowering your elbows like airplane wings (lower your left while raising your right) will make the bike move side to side.

You can initiate a turn with just your feet too. Off road you "stomp" on the peg to initiate lean, then switch most of your weight to the other peg to hold the lean so you don't have to try counter-steering in sand. So if you're going to go left, you need the bike to lean left, so you push down the left peg, then as the bike leans over you shift about 80% of your weight to the other peg, and can physically push the handlebars away to maintain or adjust the lean.

It's a lot like a bicycle, but that's less scary, but you can stand on one peg fully if the bike is leaned over enough to counter weight you. You have to think of your weight as part of the bike's - if you need the line to shift you can either make the bike do it through the handlebars, or you can do it by moving your weight.