Keep track of who gives you what, I made a spreadsheet of all of our guests invited and have added what they've given us to the spreadsheet by their name. Include the $ amount for checks, cash, and gift cards if you're going to be exact in your thank you. I also added when I wrote a thank you note.
Write Thank-You notes as SOON as you get the gifts, that way they don't pile up!
Keep any and all gift receipts you receive, even on items you know you'll keep. At least until you use the item a couple of times. I have a manilla envelope full of gift receipts from things so that they're all in the same spot and not easily lost.
Do the same thing with gift cards/checks/cash! I have a manilla envelope for all of these items as well. FH and I are going to bring cash on our honeymoon so that we know exactly how much we have to spend, and will deposit the cash afterwards into a "fun" bank account vs savings or spending. We will probably use it for rainy day fun or if we realize we really wanted something that we forgot to register for.
Speaking of checks, cash them or deposit them sooner vs later, as the people who wrote them typically will assume that amount will be deducted from their bank account sooner vs. later.
Lastly, don't forget to hydrate well before your wedding, and create a couple of different times throughout your day that are designated times for you and FH to use the restroom. It doesn't have to happen at that time, but this will give you wiggle room with your schedule so that when nature calls, you don't have to stress.
Like I said, these are fairly obvious, but I thought I could maybe help out any other soon-to-be brides & grooms!