This is like a huge mash up of all the advice I've ever gotten. Don't waste your time researching all this "How to write" crap because eventually it'll all start sounding the same. Save the hassle and just watch a few videos like this one and start writing, and keep writing.
Here's another from the same youtube channel, if you can't tell I really like these guys :P
and eventually we'll all become crazy playing out guitars and rambling about something while naked on our bed.