In a straight and level flight the collective is the first flight instrument which will make the helicopter climb
As always with flight instruments, never increase the collective abruptly but apply smooth movements
The pedals end the cyclic will be used to make adjustments.
To enter a climb in a helicopter while maintaining airspeed, the first actions are increasing the collective and adjusting the pedals as necessary to maintain a centered ball in the skid indicator.
From a straight and level flight at 3500 feets, the helicopter climbs and the speed remains constant
Then adjust the attitude with the cyclic.
Usually, the lead is 10 percent of the climb rate. For example, if the climb rate is 1000 feet per minute (fpm), you should lead the level-off by 100 feet