How can I increase my typing speed?

Obviously you already know where to put your fingers on a qwerty keyboard, so software is not what you need. Just set up some exercises with a stopwatch or timer. Compose some paragraphs, count the words or keystrokes or whatever, and decide what would be satisfactory for you to fit into one minute. Then start speed practicing until you nail it in one minute w no errors. Make sure you use at least a small variety of compositions that include making use of every key, numbers, shifts, punctuation too.