Your first task is to get rid of the delay()s in your program because they will cause the program to be blocked from running whilst they occur.
Have a look at Using millis() for timing. A beginners guide, Several things at the same time and look at the BlinkWithoutDelay example in the IDE.
Using millis() for timing needs a different approach than simply using the delay() function but allows the program to run freely without stalling. You cannot, however, just pop millis() into the existing program. It will need restructuring.