The best way to stick to your training, especially if you are on your own is to make a plan and follow a program. I like monthly programs (or 4 weekly blocks) for a couple of reasons:
Normally after 4 weeks, most people if you have been progressively overloading, need a de-load week (which means lighter weight and or less reps for 1 week).
To keep variety in your training program
It is easy to let "how you feel" dictate how your training session goes. This is not a good idea if you want to get any type of consistent results. A lot of the time, not many people feel motivated and ready to PR their lifts every training session. If you follow a periodised training plan and stick to the plan regardless of your motivation levels, then you get the work done, and leave feeling productive and satisfied.
Time dictates the frequency of sessions per week. If you only have time for 2-3 training sessions per week, I suggest only weight training and full body (mostly compound exercises) each time to get maximum results in this time frame.
This could look something like:
Standing Shoulder Press
DB Chest Press
Lunges DB or BB
Dips or Push Ups
Woodchop High to Low
DB Shoulder Press
The rep ranges for more technical exercises (back squats, classic deadlift, chin ups and dips can be lower (4-8 reps), to focus on strength and technique), while the easier exercises can have a higher rep range (8-15 reps). 2-4 working sets normally is the right amount.
If you have more time to spend training at home or in the gym, then a 4 day split of upper body, lower body works well, using the above rules, and if you have specific goals- for example to grow your glutes, then you can add more of these exercises into your lower body day.
Cardio is great to do outdoors, with the bonus on Vitamin D- just walking with intention works very well.
Diet is very important also especially for performance and recovery. A flexible approach is the best way to maintain any weight loss (if this is your goal). Keep it simple and focus on getting in protein at each main meal, add least 2-3 serves of veg or salad at each meal, some carbs (they are definitely NOT the enemy- keep them around your training window), and a little healthy fat. Fresh food is always better, keep up the variety and drink a lot of water daily and you are on the right track.
For more information on program design, or if you are looking for a qualified professional to design your program, please contact me - firstname.lastname@example.org. I have been following monthly program for the last 5 years with excellent results.