Taking a total stab in the dark here, I'm guessing that by 'toning up' you really mean keeping your already (I'm assuming) lean build, and getting a bit more muscle definition.
Judging by your posted weight, and the few pictures that provide any hints, I'm guessing you don't have much muscle right now, so there's not much to work with in terms of toning up.
Keep in mind I'm not judging you at all, just trying to figure out what you mean.
Assuming that I'm right, you should probably, for the moment, just focus on what you want to see.
Want bigger, more noticeable, toned arms? Do bicep and tricep weight exercises two or three times a week. Want a bigger, more defined chest? Focus on chest exercises twice a week. Want a bigger back? Want bigger thighs? All the same. Just focus on working those out in the gym, but try for twice a week.
If all you want is certain muscle groups to improve, but still want to work on everything else, go on Bodybuilding.com and do a search for exercises for the body part you really care about. There will definitely be a bunch of routines balanced to get that one part to grow, but still maintain strength in other areas.
You're probably young enough that your metabolism is fired up. Unless you're noticeably putting on weight with what you're eating right now, you probably don't need to worry about changing your diet. Unless you want abs, and you don't already have them. If that's the case, diet matters, a lot. But if that's what you want, create a new thread asking everyone how to get abs.
Keep in mind I'm not a trainer, so take what I say with a big grain of salt.
Based on your current build and weight, I would really guess that you just need to work a lot harder and with a lot more intensity to get what you want. Assuming I was right in guessing what you want.
Another approach (just to make this a really long winded reply) would be to hire a decent (expensive) trainer for a couple of hours, just to give you a reality check on how hard you should be working, and what types of things you should be doing.