Use WASD keys to move around and your darts will shoot toward where your mouse is and they will only shoot if the bloons are in radius of the monkey. You can increase the radius by purchasing the upgrade 'Long Range Darts' and 'Enhanced Eyesight'. 'Sharp Shots' and 'Razor Sharp Shots' Increase the amount of bloons the dart can pop in one go. The upgrades 'Quick Shots' and 'Even Quicker Shots' increase the fire rate at whick the monkey throws the darts at.