Let me tell you a true-ass story: one day, probably in the middle of my third trimester, I went to work in flip flops because literally no other shoes fit my very swollen feet. Fortunately my office was cool with this (mainly, I suspect, because my job required no meetings with people outside of the office), but it was still annoying, not to mention surprising since I never got swollen during my first pregnancy. Things got even more surprising when, before lunch hour, the flip flops no longer fit. That's right: over the course of a couple hours my feet swelled so much that flip flops were too much to ask. I got weepy, my very supportive office-wife offered sympathy (I suspect while trying not to laugh) and I carefully shuffled to the H&M across the street. I normally wear a size 8. In order to get shoes wide enough (even shoes made with stretch material) I had to go with a 10. And a half.

So prepare for this possibility. You're going to want a pair of comfy shoes at this point anyway, so you might as well.

Not only will your waddle become more pronounced in your third trimester (slowly, without you necessarily realizing it) but you will need to take what I always referred to as "huff and puff" breaks. It's nothing to do with cigarettes because please don't smoke while you're pregnant. Huff and puff breaks are the times when you have to stop even low-energy activities (like walking at a snail's pace) because you're out of breath.

It's totally normal and not an indication that you're suddenly really out of shape, either. The baby is getting bigger and pressing up against your lungs. If your baby is like my first baby, they will do this starting in the second trimester, and it will get really, really old by the third.

Third trimester is likely to bring with it random aches and pains, including back pain, hip pain, butt pain (no, really) and Braxton Hicks contractions. A heating pad won't magically make any of these things go away, but they can help you though all of them.

Also it's just a good thing to have in the house even if you're not pregnant. Who doesn't love a soothing heating pad pressed against a tight, stressed out lower back?

You may have been doing this before now, but the constant peeing is almost certainly going to be cranked up a notch as your ever-expanding baby encroaches on your bladder. It's just good to know where the restrooms are beforehand, so you waste no time when nature calls.

By my third trimester, even some of my maternity shirts were starting to ride up and show the world my pregnant belly. Also I had outgrown a ton of stuff, which meant not only did I only have, like, five viable outfits, but they were pushed to their limit. I was exhausted, physically and mentally, and a lot of the time it showed (especially since I had few f*cks to give about doing hair and makeup).

I'm not saying I was a heinous trollbeast during my third trimester (or that you will be) but if you're anything like me you'll probably be sort of over it soon and feel less than awesome about your physical appearance. That's normal. Just remember that you owe nothing to no one regarding your physical appearance. "Beauty" is not the price of female admission under any circumstances, including during pregnancy.

Your care provider will likely let you know exactly how they want you to track things (there are different schools of thought on how many are appropriate in a given period), but the third trimester is a good time to start paying particular attention to your baby's movements. I'm also here to tell you not to freak out about the precise number of kicks or fastidiously monitoring every moment of every day. This is more about getting a general idea of your baby's activities.

Certainly you don't have to worry about inducing at this point (seriously, please don't) but you are almost certainly going to reach a point in your pregnancy when you're going to start thinking about how to evict your little tenant, either as you uncomfortably approach your due date or frantically overshoot it. This will be when you start trying to take matters into your own hands by desperately researching every old wive's tale you saw on a mommy blog.

A little information in a time of desperation isn't a good thing. So start reading up on "end of pregnancy" information now rather than later. This will give you the most complete overview of what is within your power, what isn't, and what might work best for you.

I am aware that, in some cultures, buying anything before a baby is born is considered a bad omen and should be avoided at all costs. In those instances, I'm sure you have a system in place to get what you need when you need it. But if you do not have an cultural taboos about purchasing items ahead of time, I highly recommend having the essentials — few articles of clothing, diapers, a car seat (if you have a car) a place to sleep, bottles, blankets, that sort of thing. You don't have to decorate your whole nursery, but it's nice not to have to worry about the necessary items when you're also worrying about a newborn.

"I have time!" I kept telling myself... right through to my delivery.

Yes, mom who is newly in her third trimester: you do have time to choose a pediatrician, but less time than you think. Start looking now and you can be all leisurely about it. Trust me, you don't want to be asked in the hospital, "So, who is your pediatrician?" and just smile at the staff blankly. Because newborn appointments start right away and occur all the damn time for the first couple months. Even if you just pick one at random at first, you can always switch later on, but you should have someone to jot down on all the paperwork.

(Pro-tip: talk to local moms. They are a wealth of information.)

OK, you don't have to do this right away, but don't put it off too long. I can tell you from experience that packing a hospital bag while in labor is the opposite of fun.

The last thing you are going to want to do is cook and/or grocery shop while you have an itty bitty baby. It may, in fact, be impossible to do either of those things in the early days of new-mom life. Solution? If you make a freezer meal a week you will have 13+ meals ready to go for those days you just can't, either literally or hyperbolically.

While this isn't strictly speaking necessary (the first time I went to either of my hospitals is when I was ready to deliver) many parents-to-be find a "dry run" to be comforting. Some hospital tours may even be accompanied with a parenting course or baby first-aid class. If this sounds like something you would dig, look into it now so that you can schedule it before your due date.

Not only is this necessary to establish the nitty gritty of maternity leave, but it's just good to have a plan in place to make your transition back to the office as smooth as possible. You're going to have enough to deal with when you come back without having to figure out who screwed up what in her absence because no one knew WTF the plan was.

The third trimester can be tough. Mentally I think it can actually be the hardest trimester. And yes, there's going to be things to do (like, you know, pretty much all the things I listed above) but don't feel bad about taking a good chunk of your free time this trimester to just rest up and relax. Your body is doing a ton of work and it's OK to let that be "what you're doing" on a particular evening or afternoon.

Be kind to yourself, is what I'm saying.

Whether this is your first baby or your seventh, things are about to change. Take some time to enjoy the life you've enjoyed up until this point, because it's going to be a while before you and your newborn are going to be able to be out and about (at least in the way to which you are accustomed). During my first pregnancy, this meant a rooftop dinner with my husband and best friends. During my second pregnancy, it meant a special trip to the zoo with my 2-year-old son. Both of those memories are treasured because even though my children only served to improve my life, it was nice to celebrate what had been before they existed, too.

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