Two words: high intensity. Shorten your reps a lot, keep them in your optimal leverage range, and go heavy. To do that effectively, you need to start using a power rack, with the cross bars set right at the bottom of your strongest range. Bench presses will reflect this change in routine: if you were doing, sat, 180lb benches before, you should be able to do more reps in less time at 225 or 250 the very first time you adopt this approach. Same with shoulder presses. For biceps, the best exercise is a hanging weighted chin, palms in: get yourself a chain belt, strap 10lbs to it, move a bench under the chinning bar, 'hop' up into a contracted position at the top of your strongest range and hang there for 30 seconds. As soon as you can do that, add 5lbs to your weight next time, and so on.
Another very good exercise for both pecs and triceps: find a dipping rack, add 50-75 lbs to your chain belt, and do very, very short range dips, as many as you can up to failure. Next time, add another 10lbs, and do at least as many in at least as short a time.
A couple of points about this routine (the so-called 'Power Factor' system due to Sisco and Little, named for the particular ratio they arrive at to quantify performance, yielding a number that you should try to increase every workout). First of all, it is very effective... and very unpleasant. It is no fun at all, and can be a bit demoralizing if you wake up feeling not particularly aggressive or 'predatory', as I think of it, toward the weights. But nothing comes for free, eh? Second, you cannot do this workout frequently. Once you get to be shifting major weights, 300+ in your short range benches and so on, you are going to want to take at least three weeks between working the same muscle group. One of the keys to this, or any of the various high intensity training regimes out there, is recovery time. And the older you are, the longer you need to take to recover. If you go back too soon, you'll know it: your numbers will go down, not up. Third, you really do want to keep track of how many reps per unit time you're doing. Ideally, what you should find is that, over time, and with proper recovery, you'll be able to shift increasing amounts of weight per unit time, over the same number of reps. It helps enormously to keep track of your numbers and of the time, using the stopwatch function of your sports watch.
So you have to maintain both a conquistador attitude to the iron, and exercise self-restraint—particularly hard to do when you've had a perfect 'breakthrough' workout and want to ramp it up a week later. But if you can balance the two somewhat contradictory attitudes, you'll gain strength very, very quickly and efficiently.