When you're busy getting the most out of your training time is important. There are several questions to ask yourself before you train on a given day.
1. Remind Yourself of Your Goal
Firstly you should have a goal. Stop reading now, if you don't have a clearly defined goal with a measure and a deadline. Go and do this, then come back and keep reading.
This goal should be constantly updated and refined as your abilities change and your focus changes. What is important to you at one time may not be the same 6 months later. That's OK, and normal, but should be reflected in your updated goal setting.
2. Have a Plan
Once you have a goal (or goals) you'll need to develop a plan to achieve these. Your plan should be at the very least a weekly plan, stating what you will do, and when, in order to achieve your goals. You might like to develop a longer term plan 1-3 months is useful to see where your current training fits into the overall picture.
Most importantly is that in your plan should be everything you'll need to achieve that goal. So if the goal is to drop 10kgs, then obviously scheduling workout time is important, but it's not the only thing. Also in your plan should be the actions you'll take towards your nutrition, sessions to measure and reassess the goal, mobility and recovery sessions to keep your body in good health, and even planning sleep, which if you're running low on, will hamper all these other contributors to the goal. All are equally important factors in achieving this goal.
Don't get caught in the trap that if you're not working out you're not getting closer to the goal. Sometimes the best breakthroughs are made sitting and talking to your coach.
3. Always Perform Movement Prep before Your Workout
If a training session is called for then you better get your body prepped properly. No, the walk from the office isn't sufficient. No, 5 minutes on the bike won't cut it. No, that limp quad stretch is useless for preparing you to really move!
Your Movement Prep must contain (at least) the movements you will be doing in your programmed session (but should ideally cover your entire body). You'll work from some easier movements up to the intensity that you'll use within the workout. If you don't have a light sweat going and a raised heart rate by the end of your movement prep then you're not finished. You shouldn't feel much difference between the last few minutes of your movement prep and the beginning of your sweaty session.
4. Keep a Record of What Actually Happened
The other part of no.2 is that once you have the plan, and perform the plan, you'll need to record what you did and how that went. This helps create a feedback loop on what is working or not working. At its most basic it means recording your sets, weights, and general energy levels, but it can and should be a little more comprehensive than that.
For the best results though go a bit further. Make notes on how you felt before, during and after that workout. This could bring to light where nutrition could be improved, whether you're drinking enough water during training, and whether you performed a suitable cool down.
Additional information like this helps round out 'holes' in your programme and provides much more evidence over why you've achieved a certain result and nor another. These records can then be used when planning towards your next goals. You'll now have a better idea on what works for you, and that ultimately is the only thing needed to boost your workout productivity.