You should give yourself some clear goals and work towards them. You said you did legs and abs today, with some cardio afterwards. Depending on what you classify as cardio you could already be shooting yourself in the foot. You should think of training as evolving your body, you're trying to go in both directions here, it's not going to work. It's very hard to get good in all aspects of performance even when training optimally, messing around usually just leads to burning out and discouragement. Training is just as much about doing it smart as doing it with intensity.
1. Separate the type of training you are doing. This is counter to what most people will say but it is the quickest and best way to get results. Think about it, when you try to hurry and fumble about trying to learn or do 5 different things at once, you end up taking shortcuts and messing things up. Take it step by step and everything will be done to the best of your ability and properly. This is key, when training I don't train just to train, I train to get better. If I'm not going to the best of my ability then I'm not making progress, and I'm wasting time. When you train, focus on one thing at a time, be it technique, speed, stamina, strength, flexibility or whatever. Making proper progress in one will help out the others without the need for mixing yourself up.
This means that if you're doing weights, do weights and don't do cardio straight after. Say you pushed yourself with some squats, great! You're sending stimulus to your muscles to get bigger and stronger, you need to be able to exert more energy! Now not 30 minutes later your huffing on a treadmill, uh oh... now you're telling them to streamline and be more energy efficient. You're sending mixed messages and getting nowhere. You need to give your body time to act on these messages before cancelling them out with another.
Do weights one day, eat, sleep, recover... Now cardio the next day, eat sleep recover. Repeat. Now you are giving your body time to recover and react to the stimuli your sending it, then sending it another which it can react to in turn. Instead of doing both and getting nowhere. If you've got nothing going on you could split your workout into weight or running in the early morning, eat and have a nap, wake up and later on in the day you could do the other. You're still giving your body the building blocks it needs and some time to follow the instructions your exercise has given it, instead of just sending two sets of contradictory instructions at once.
2. What type of cardio are you doing? There is no way you can train with any kind of intensity for 8 hours. Cardio is cardio, as in cardiovascular endurance. You push your heart hard for 8 hours and just about anyone is liable to suffer a heart attack. If you're saying cardio but really mean walking or slow jog on the treadmill then you're really just burning calories, which is fine, but why not take an easier and more effective approach and just cut some of the calories you still in and save yourself from wearing out your knee joints unnecessarily. Energy is at a premium, especially if you're trying to excel in multiple opposing areas of fitness. The hours of unnecessary cardio just serve to wear out your body so come tomorrow or later in the day when you hit the weights you're not at your peak and can't push yourself to make those gains in the strength department.
One of the hardest things to realise is that you have to be as efficient in your training as possible. Which seems to fly in the face of what most people think of when they think exercise. It's all about wasting as much energy as possible right? This can get you to a decent level, but if your the type of person that wants to do cardio for 8 hours, you're probably not the kind of person that wants average results.
3. Use the 90/10 rule. 90% or your results come from 10% of your training. Focus on the main thing you are training, and get rid of the mess. If you train legs, do your squats and deadlifts. These two moves will give you 90% of your leg development, now you could waste another hour hitting the leg press, calf raises, hack squats, glute ham raise and whatever else for the last 10%. Or you could save all that effort go home, recover and put it towards your cardio later, giving you a better cardio workout. Again, efficiency leaves you with better results, quicker.
Go home, eat your steak and vegies. Maybe a protein shake, get enough rest. Thats 90% of your recovery, you could waste your time and money getting preworkouts, intra-workouts, post workout recoverys, bcaa's, this and that new product that boosts your gains! etc etc. It's not lies, but so many people waste their time and money on that, the stuff that gives you 10% without nailing the easier 90%.
These are the 3 main principles I've been trying to follow with my training ever since I started researching and taking my training more serious. It's the best advice I've ever been given so I'm just taking the time to pass it on. Most people probably already know a lot of this but it's always good to be reminded that it is the simple things that get the best results. Ever since taking this advice seriously I've gone from 116kg barely being about to squat 70kg to what was surely above parallel, bench press 80ish badly and deadlift 90kg (who knows what I could run, I didn't run back then) to 92kg. Yesterday I hit a PB of 122.5 kg squat ass to grass for 3 sets of 5. Deadlift 175kg for 5 reps and bench (properly) pause reps touching sternum 110 kg 3x5. I'm still nowhere near great at running, never have been, but I can now run 5km in under 25 min. It's good for me, but I'm still improving and will be for a long while hopefully. I hit the weights mon/wed/fri for full body workouts and run tue/thurs after training muay thai. I'm not trying to brag, I don't think any of the figures are anything really that impressive, just trying to lend some more credence to the ramblings I just spent half an hour typing into an random internet forum I guess. Take it or leave it?