<--Started at 155 earlier this year, currently at 188 and have gotten considerably stronger. I don't care about this particularly, but you may that I still have a six pack. I am definitely still a beginner to lifting, but I've been seriously training at other things for about three years. As such, take what I have to say with a grain of salt:
First, you should start counting sets. And better yet, you should put yourself on some sort of program. You don't have to follow the program exactly if you don't have access to the equipment etc. Read the posts from guys who have gotten big and strong on here (not me). When I walk into the gym every day, I know more or less exactly what I'll be doing and how much of it I'll be doing.
Three times a week is sub-optimal. Like guys have said here, find a split that you like and that the person propogating it has a physique that you admire/appreciate. As much as people are recommending the "Do this routine," you might be better served with 5/3/1 because it would address your problem of not knowing HOW to progress.
I think that KoB's "Do this routine" assumes that the person doing it knows how to progressively overload their muscular capacity. 5/3/1 makes no such assumption--it gives you rep and set ranges and includes the load that Wendler suggests you do.
You can do the 5/3/1 on a 4-day split. If you do so, one thing worth doing would be to read some of the training logs that others have put up who use 5/3/1. It's very popular on these boards.
Next is eating. 2400 might be "above maintenance" by calculators, but you need to start listening to your body. When I was 155, I was eating in the 4k-5k range every single day. Also, what are you eating? What does a day of food look like for you? You should be able to give a basic calorie and macronutrient breakdown of your daily diet.
Lastly, start writing stuff down. Write down what weights you use. Write down your workouts. Write down what you ate each day.