What to do and how long to do it your afterward success or not success will tell you exactly.
The key is time and experimentation. I will tell you, WBTB is the best way to become lucid if you combine it with WILD, there is almost 100% success rate, but only if you do it right.
There are just some days that are perfect for LD’ing and everything is going well and you can become lucid very easily, but these days are just the prof that it’s possible.
I wouldn’t recommend the PC, rather print something interesting and read it then sitting or laying before the monitor… If you don’t need much to wake up then just do what noobdreamer and Laurelindo said… There are natural non destructive ways of becoming awake and conscious!