Combo's? That is pretty broad, it is also hard for me to explain how to do some. What kind of combo's do you mean??? Punching,kicking, punching kicking, kicking punching kicking...etc...
This is a boxing forum, so I'm guessing he is looking for punching Keep em simple, don't open yourself up, don't hit where his hands are. Make sure they flow together and create and exploit openings.
It depends on who against. One I like a lot at the moment is against people who over-parry the jab with their rear hand - very common in my experience... Jab to lead hook (What we call Progressive Indirect Attack in JKD) / rear uppercut / lead hook / rear straight.
Nope, the jab is with the lead and then the hook is done with the same hand. The important bit that Yoda mentioned is that the opponent over-uses the rear hand to parry the jab thus leaving a potential gap for the hook. Quite often I find that you catch people with this if you set it up with a couple of jabs to get their reaction then fake a jab and switch to the hook en route . Cougar - all combos have their time and place and its not just speed that counts. 3 or 4 very rapid punches are just as ineffective as a single punch if they don't reach their mark. The use of broken timing seems to open up some of the combos that might otherwise seem slow for instance...
One thing about combination punching is to vary the height and angle of the punch. One of my favourites would be lead hook to body/lead hook to head. I find this combo works best when you're under pressure and can be used immediately after you slip to the outside. Quote Andrew - "don't hit where his hands are" I would nt say this is entirely correct. Aiming for the hands/forearms can force your opponent to be on the defensive and if your lucky you will hit him with a stop hit as moves his hand from the guard position to hit you. Also when using combos you must vary them by changing the strike and also the rythm. ie jab - cross jab - jab - cross jab - cross - jab cross - jab
Cougar, jabs can be both and more. They can be used to judge distance, to set up other punches, on their own, in combination, in multiple shots, faked etc etc... There aren't any hard an fast rules about how to utilize them they're just one weapon in the arsenal. If you can hit hard with a jab you might not need anything else. However if you're slighlty out of range, you don't hit that hard, you miss or you target is resillient for example then you need to be able to pull something else out of the bag. As I mentioned earlier you can also fake the jab (as with any other tool) in order to draw a reaction and then use your bigger guns. As johndoch said, you should also vary the height of the jab (and any other technique). The jab is just a tool there are numerous ways of putting it to use.