I am currently trying to do this three times a week. I write down my chosen variation with any subvariations and, only then, check them against the book. I also explicitly give myself a total of one hour to solve three problems, taking most time pressure off of me so I can really just focus on seeing all the candidate moves, visualizing each variation, and trying to pick the very best move. One is called " Analyze 3 positions for 20 minutes each." In this exercise, the point is to improve calculation and visualization skills, so I use a more challenging tactics set (currently, Chess Training Pocket Book by GM Alburt) and I set the problems up on my physical chess board. In the spreadsheet above, I actually have two different types of tactics training that I do. Besides that, popular chess trainers like NM Dan Heisman highly recommend weak players do loads of simple tactics problems before spending a lot of time on other aspects of their game play.
I've made solving tactics problems my main chess activity because I knew from reviewing my games that I was losing for tactical reasons: Hanging a piece or a pawn falling for a straightforward 2-3 move tactic or, simply mis-counting a series of trades.
Over the past eighteen months I've logged over 1400 chess actions in my spreadsheet, actions such as playing a slow OTB game, reviewing a master game, doing a visualization exercise, but mostly, solving tactics problems. When I started my serious chess training program in July 2013, I created a Google Docs spreadsheet for tracking all of my chess activity.