I got married 9 (gasp) years ago and the one piece of advice I won't forget and have passed on when asked is: choose 3 words you want to describe your wedding. This advice is so simple and magical and practical all at the same time. At first it seems a little hokey, but the more Ben (then fiance, now husband) and I talked about it the more helpful it was. We were so overwhelmed with all the decisions we had to make and I was pulled in so many directions I didn't know how to choose anything.
Then we picked 3 words.
It brought things into focus - what was important to us? What feeling did we want our guests to have when they experienced this day with us? Suddenly we knew which flowers made sense and what location would fit us best. It works no matter the level of DIY projects you have, how big or how small the wedding will be, how much or little money you spend. Those 3 words can be a place you can come back to over and over to give you clarity and direction. They also serve as a great way to constantly be reminded why you're planning this celebration to begin with.
PS I also was told to try sitting backwards on the toilet when the time came (I had a 5 foot train)... and that was pretty amazingly helpful. Didn't need to experience going to the bathroom with my 5 closest friends watching! (I: And as close as we are as sisters, and as her MOH, I appreciated skipping that particular bonding experience too.) So if we haven't proven it already, we are here for you.