I stay organized and on top of everything by making schedules and lists. Lots and lots of lists and a detailed schedule. I do it for everything in my life, not just the gym. Sometimes I even have to organize my day by the hour to make sure that I stay on track to get everything I need to, done. To Do lists help as well and it's very satisfying to be able to cross things off of it. Look at your whole week and mark down the days that you will go to the gym. You then have to commit to the schedule that you have created for yourself.
Make a meal schedule. Decide what times you will eat throughout the day. Since I eat 5 times, I figured out what times to eat during the day that works with my schedule (the times vary a little, but they are about 7 am, 9 am, 12 pm, 4 pm, 7 pm). I prepare all the components of my meals in the morning, before I go to work. Keeping everything under control is important because not knowing what you're going to eat in advance will lead to bad or lazy food choices.
The gym is a time commitment. Once you realize and accept what that means, then things will get easier. For me, sometimes it means I work 8-6, come home and go straight to the gym until 8 pm. Or sometimes I come home and wait until 8 and go to the gym until 10 or 11 pm. Those extra two hours I could spend relaxing, or getting other things done, but I choose not to. The gym is a priority for me so the other things can wait until after I'm done. It also means that I make time on the weekends for the gym because those the two days I definitely have time for it.
Set realistic goals for yourself. You initial goals are not the same as realistic ones. As you come to learn more about fitness and your own body, you may be able to develop more realistic goals for yourself. You should still always push yourself to achieve more! Realistic goals also include how many times you can make it to the gym in a week. It might only be 3 or 4 days, or it might be 6 based on your schedule. Knowing yourself and your bad habits and make sure that you go the extra mile to break the habits and develop useful ones. The more you know and realize, the better prepared you will be.
So to sum things up, I manage to fit everything into a busy schedule because I stay super organized (I have a notebook devoted to scheduling and lists, as well as a planner and to do pad), I realize that I have to put the gym towards the top of my priority list (this means occasionally bailing on the fun stuff too), and I was determined to learn enough about fitness so that I could figure out how to fit it into my life and be completely prepared.
I know I'm forgetting things right now, but these are the main points I thought were important to make. Let me know if you find this useful!
P.S. Starting the day with a great breakfast is usually a great idea too!
Make the choice to do it.
And you'll go to bed feeling satisfied.
You are completely capable of doing it, you just have to realize it first.