just a few of my training techniques.
For the Begginer i would recommend using a single fly, with around 10k-15k weight, stand facing away from the weights and far enough so that the weights dont crash down.
Throw jabs untill it burns, swap arms and throw jabs with the other till it burns, then go back to the first arm and throw crosses till it burns, then do the other arm crosses, then stand side on and throw hooks till it burns, then swap arms, rest for a min or 2 then do again.
use a low fly to do uppercuts (if you want to learn these) for general defence id say learn the hooks and crosses the most as these are what will knock a guy out in 1 compared to a jab, and an uppercut is fairly hard to land and can be seen coming a mile off by anyone who knows how to fight (unless using a kickboxing uppercut and jamming your weight behind it but this is very different from what people recognise as a boxing uppercut.
different size people will need different weights but its important to throw explosive movements rather than the slow muscle building ones. each punch should work, in this order: toes, legs abs, chest, shoulder arm. in each throw.
when throwing a punch the arm is only tensed at the final few inches, if you was to tense it the whole swing then the bicep will counter the movement in the arm limiting speed, and force applied = speed x weight (simplified) (speed and weight both being generated by the moving of the whole body and not from the arm.
Explosive uppercuts can be trained using a dumbell of around 10-20k and holding it in a gaurd possition explode upwards to an imaginary chin infront of you, for right uppercuts use your right foot to extend onto its toes, push up with the calf drop your left shoulder down, right shoulder pushes forwards and up as the arm comes up with a locked elbow, with this punch the arm does NO work, its just a weapon held stiff that the body and legs push into the opponent.
rather than bench press, do explosive press ups, start in the fully lowered possition and explode as hard as you can upwards while breathing out hard, bounce high and on the landing go streight back into the low position.
for wing chun style streight punches do the same as above but rather than having your arms in a bench press position, keep the hands either side of where your solar plexus would be and tuck the elbows into the body, this helps the arm and shoulder generate alot of power in a short space, much like bruce lee could with his 1 inch punches.