It's very difficult with a touchpad unless one is left handed. Keys on the right, aim on the left: bad for the 90% of us. I should look for my mouse. I know I have one somewhere.
It's not only hard, it's impossible to play with my touchpad. It has some kind of anti-interference detection so that it can't be moved/clicked shortly after typing on the keyboard, "smart-check" they call it. This "feature" can't be turned off completetly! It just has a slider going from min-max where max requires almost one second delay after typing and min only prevents simultaneous motion/typing, which is what you need if you want to move+shoot simultaneously in this game. Lenovo+synaptics crap.