GMAT Strategy

The past couple of weeks I have been studying GMAT concepts and going over GMAT practice problems in both PR and Kaplan. I've spent a day or two on each chapter just reading through the material, refreshing my memory on the various math and verbal topics, and giving the problems a shot. I've pretty much covered all of PR except the last "bin" of quant and verbal. I've also gone through problem solving, ds, and word problems in Kaplan so far, and I plan to finish the Kaplan book by the end of the week.

My question is: how serious should I be taking my GMAT prep at this point? At first I thought it would be good enough if I read every chapter and worked through every problem. But now I'm getting a bit concerned.

Am I suppose to be timing myself for each problem at this stage? Or wait until I start OG?

Am I suppose to be keeing an "error log" at this stage (not even sure what that is)?

Am I suppose to be copying the problems I got wrong onto a Word documenet?

I'm not quite sure. I'm shooting for a fairly high GMAT score, but I feel like this might be a waste of time and energy if I do all of this at the beginning stages. I'm doing the problems, taking "notes"/making flashcards. Is that enough to get a 700? Or should I take this first stage a bit more serious?

Please help.
I would appreciate it (especially from those who've already taken the test and have scored 700+) Thanks1

...any thoughts?