a lot of good valuable tips and points in here but one thing was left out.
video yourself or have your friend/gf/wife someone, video tape you.
over the many years of this game, i've grown frustrated and ill to a point of making the same mistakes until i took a video of my swing. from different angles. it was then that i realized i shouldn't be dissecting other pro swings per say, but moreso my own. it's my body..and it's my swing so i needed to focus on what exactly i was doing wrong and trust me, if you do, you will find things wrong with your swing.
in my opinion this is the BEST judgement of your swing. you can have 10 people tell you what to do, what not to do but you're the best judgement of your own body. so video tape yourself.
also, i'll add one more thing...we are accustomed to not changing. whether it's our belief or our ways...but physically changing is just as demanding. your body is the most stubborn part of you. you can change your mind but you can't change your body over night. after you video yourself and see for yourself what mistakes your making and what changes need to be made, train your swing (body) to CHANGE. then and only then you'll know that what you're doing is right....for you.
i love golf tips...can't get enough of it...but at the end of the day...we all swing differently so take that as the main account. you train your swing to fit your style.
i grew up surfing and people always ask me, teach me how to surf. i always say, you just gotta get out there and surf as much as you can to get better. aside from the small fundamentals on how to paddle and push yourself up...the rest is up to you.