1) Define "gym work, mainly legs" - which exercises, number of reps etc.
2) Once you have read the book, re-read it. Then ask questions if there are any points that need clarification.
3) If you are just getting started then following the same training plan week to week is a good idea. Linear progression will occur for a long while. Test your power regularly and when you stop progressing then look at changing things. Random training yields random results.
4) Because you live in Australia you have little excuse not to train outside all year long. Unless you live in the Australian Alps any complaint of the weather will have you branded a pussy.
5) Remember at all time the paradox of training, that is, training makes you weak. It's the rest and recovery that will yield the improvement. Skip on eating properly and sleeping properly and it will delay adaptation and improvement. Ignore all "diets" like the paleo diet, no carb diet, all carb diet, all fruit, the fasting diet, high protein, blah blah blah. Fresh food, mostly plants, minimal processing, don't skimp on fats (exception being trans-fats).
6) Aim for better power, skills, handling etc, not the "look" of a cyclist. If you apply yourself to training the cyclist "look" will come of its own accord. Forcing this by stupid diets or training practices will hamper true progression.
7) If you want to waste your money on a month subscription fee for an unessecary service then the above post has some good links for you.
Point 1 - do all single leg workouts, step up, one leg squats etc, mainly mid weight with 10 - 12 reps, noticed from Watt classes my left leg needs to be built up and generally my pedal stroke shows 48% left 52% right but a nice sausage shape on the axis.