Sometimes people just have to wait. Do what you can: ask for help, consolidate your steps, but in the end there is only so much even the gods can do. Accepting limitations is an important part of growth. Often we become stressed or agitated, as the chattering mind thinks that somehow this means you are “doing” something about it, something productive. It cannot abide relaxing, because it is convinced this means you are giving up. Indeed you are giving up - you are giving up the illusion of control. Being upset or stressed does not make the kitchen move faster nor does it make you any more able to do your job; if anything, it lessens your effectiveness. So relax. Be the calm in the eye of the storm.
Not to use a pun, but a good deal of waiting tables does actually involve, well, waiting. I have to wait on hot fries, I have to wait on the bar to make my chocolate espresso martini, I have to wait on bread to be sliced, I have to wait on the bakery to plate my desserts, I have to wait on the barista to make my cappuccino, etc., etc. And when you're busy, every second you're stuck waiting feels like an eternity. You know that while you're waiting for that cappuccino someone at one of your tables needs something, and odds are they're getting kind of pissed off wondering just where the f you are (I think guests subconsciously think that if I'm not immediately at their beck and call it's because I'm off just dicking around somewhere, talking with my friends or flirting with the hostesses or something. I don't think it would ever register with someone that isn't already in the industry that there are things out of my control too). And just as every second you're waiting feels like an eternity, every second the guest doesn't have that extra sauce or soda refill or whatever feels like an eternity to them too. The thing is, when you're busy it's probably because the restaurant's full, so it's very likely that the cook or the baker or the barista or whomever else is busy too. So it's pretty likely you'll be kept waiting for something.
Of all the things that can stress me out at work, waiting probably tops the list. The main things is because of the disconnect between where I want/need to be and where I am. I need to be over there, and I'm stuck here. It's like waiting in line at the movies or waiting for the elevator to the nth degree (at least when I'm waiting for the elevator someone else isn't complaining to my boss that they don't have a fresh diet coke). What I've gradually learned to do is to just embrace it, to accept that if I need that bread I have two choices: continue to wait, or go back to my table and tell them that it's going to be a few minutes while they slice some fresh bread (of course, there are some times when, because the guest has already been waiting so long, you absolutely can not return to your section without that bread (or martini, or dessert, or whatever). You still have a course of action though, and that's to ask for help. While you're waiting for that latte one of your coworkers (or, God forbid, a manager) can swing through your section to see if anyone needs anything).
Learning how to wait properly has been one of the healthiest things I've ever done for myself, mainly because I get so many opportunities to practice it. Not just at work, but when I'm waiting for the bus, while I'm stuck in traffic, waiting for my girlfriend to do her hair and makeup, etc. The next time you're stuck waiting somewhere try just allowing yourself to wait. Accept that you can not be anywhere else but here right now, and that stressing out about it is going to succeed in nothing but raising your blood pressure. If you need that bus to get there or you're going to be late, you can either take a cab or just accept that you're going to be late. Frantically looking down the street every 30 seconds to see if the bus is coming doesn't make it come any faster (and while we're at it, re-pushing the elevator button doesn't seem to help much either). There's a wonderful freedom that comes from letting go, of just accepting your powerlessness in the situation and going with it. You should always do whatever is in your power to do but, at the end of the day, we only have control over so much.