Chris if I haven't done my workout because of anything: not enough time, sickness or even laziness should I make it up or just skip and wait for another workout day?
I'm not sure what exactly you mean.. sorry
I mean that if I haven't done my workout for example on Monday and my another training is on Wednesday should I make my Monday workout on Tuesday or at any other rest day or I should just skip this workout and keep to the schedule?
Skip it, there's no reason to do the Monday workout on a rest day, just do the lvl you were suppose to do at Monday or in other words keep to the schedule. Rest day is also very important and it's okay to skip a workout every once in a while if you weren't able to do it or something happened.
Thank you very much ;)