Depends on what you want to do. Personally I go for strength/felxibility/durability and the looks are just side effects. Here is a workout my coach gave me (mma). It's called the Royal Court.
-100 Hindu Push Ups (or as much as you can. Do them in sets of however many you can. You want to eventually hit 100 straight. So lets say you start with 25x4 and than just keep increasing the first and decreasing your last set accordingly.)
-100 Squats (same thing.... try and do it in one shot and than up the number as you get used to it)
-100 Dips (Do sets of what ever you feel like)
-Hold a the Plank for about 2-3 minutes or so.
-Bridge on using your head. Hold for about 2 mins or so.
-Finish off with Chin Ups if you can. Do as many as you can.
-Stretch
Here I'll try my best to explain each exercise (I also recommend hitting up youtube)
Hindu Push Ups- For any yoga people out there, start in the Downward Dog position. In plain english, stand up straight. Now spread your legs past shoulder with. You should have a wide base. Now keeping your feet where they are, knees streight go down on your hands so your body forms a perfect triangle. Hands at shoulder width. Now do a dive/push up. It's hard to explain but think fighter pilots when they drop like mad and than pull up in the last second before hitting the ground. You do a push up in an arch motion, and than go back. Rinse and repeat.
Squats- There are a few different variations that you can do but here is the one I do. Stand up straight, feet at shoulder width, with your hands at your side and back straight. Sink down into a squat and "row your hands" up as you do the squat. Think like you're rowing a boat.
Dips- If you have a machine, great, if not grab 2 chairs and face them together, as far apart as you need them to be. Grab the side of one chair (the seat not the side, palms facing down) and rest your feet on the seat of the other one. Your body should be in the shape of an L. Now with your back straight just dip down until your elbow is bent at about a 90 degree angel. Come back up. That's it.
Plank- This is a core exercise. Go into a push up position with your back and legs perfectly straight. Now drop down on your elbows ( I personally form a triangle with my hands under my chin) Head straight, just hold this position. If you want to mix it up, after about 30 second lift your right arm and left leg off the ground and just hold that for however long you want, and than switch. Keep switching/going back to your original.
Bridge- This works your neck and back and if you did the exercises above you should also feel it a bit in your legs/hip in the end. This is hard to describe and definitely watch out so you don't hurt yourself. USE A PILLOW FOR YOUR HEAD (unless you have an iron skull). Youtube this if you can. You essentially go into a bridge using your hands like you normally would. You arch up and find your center and technique....now lower yourself onto your head and cross your arms in across your chest. Adjust yourself and hold the position. Its okay to change the angel through out the exercise. This is probably better for people who already have some neck strength
Chin Ups- I think we all know how to do chin ups. Experiment with different grips and widths, just make sure you do them properly. (proper extensions).
Stretching- This is just as important as anything else. It relaxes your muscles, gets you a chance to cool down in the end and also tones your body. Being flexible can also come in handy other places

. I'm not saying be a yoga master but you should avoid being rigid like so many juice bags I see around. You are much more prone to hurt yourself or pull something. I won't go into details on the stretches (unless you guys want) but just stretch everything in general. Neck, shoulders, arms, core, legs...
The key in doing all exercises is BREATHING. This not only can it WILL make or break your training. Breath from your diaphragm, and breath out making a ssssshhhhhhh sound. If you want to add a bit of a twist to your routine, be explosive when you do your exercises (except for the bridge/plank obviously...no real way to be explosive there lol). Explode on your squats, dips, push ups etc.... or do the exact opposite and go slow...mix it up and find your rythm and if you decide to be exlosive or take it slow accommodate with your breathing. Hope this helps.