We had a fairly large, fairly traditional wedding.
Where we did save money:
-No wedding car. A friend offered to drive my father and I, and then my husband and I. We accepted and he put ribbons on his car.
-My dress was a sample (as in, they use it at the bridal shop for people to try on). Half the price, and really, no different. A few people had tried it on. So what?
-My shoes were marked down to £10 because one had been in a shop window and faded. Um, they're white... so one is, slightly whiter? I knew no-one would really see my shoes, and I still thought they were cute, so job done.
-Found a venue that let us serve our own booze. They did insist on professional bar staff, so it didn't get too wild, our caterer provided staff for a reasonable hourly sum. It was hard finding a venue like this though - they don't show up on page 1 of google results for 'location + wedding'. Be prepared to search. (first we looked at a marquee. That option was not cheaper where we are).
-I made my own wedding cake, but I have been properly taught, so that's a YMMV.
-No band because we actually prefer a DJ.
-I bought my bridesmaid's dresses for them, since I was choosing. I got a lovely jersey wrap dress which suited lots of figures and was forgiving with fit (so no alterations) on sale online very cheaply.
-For invitations I designed them in Word, and sent to a commercial printer who usually does business cards. I had the font raised so they looked very fancy, and I saved hundreds on every comparable 'wedding' product I've seen. If you're not happy to design, I bet you can pay for a design to be done on Etsy and they will send you the files. Pro-printers are just that - professionals. They will do amazing, high-quality work at a fraction of the price. My guy was happy to send me different weights of card to chose from. Also, buy envelopes FIRST and have the invitations sized to fit. It's very hard to find an envelope to match afterwards.
-Bought my veil on Etsy for like 1/10th the price bridal places were charging.
Basically it's a case of deciding what matters TO YOU. We wanted well fed & watered guests, a DJ, a good photographer who would do as we asked (ie butt out) and I wanted to wear a pretty dress. We got all that. We skipped stuff that I know is important to others - transport, live band, gowns for bridesmaids - but wasn't important to us.
We were also very lucky to have a wonderful aunt do the flowers, so if people offer genuine help, do accept. I know our wedding was extra special to her because she was so involved, and I think of her every time I see the beautiful flowers.
My top tip is once you know you are getting married to always be looking for things that you want/need. I saw my wedding shoes in a shop window one random day 18 months ahead. I just bought them there and then. I saw dresses in my chosen colour on sale, and got them straight away (from a regular store. They were not specifically 'bridesmaid'). This is much easier if you have a long engagement (but don't do that for the sake of saving money! We had other reasons). For example, if you want table decorations you may find they are cheap about this time of year. Same with invitations etc - don't get stung by higher prices in the new year as 'wedding season' approaches.
Don't think you need to use 'wedding' suppliers just because it's a wedding. Bridesmaid's dresses, stationery, shoes, all these things can be purchased from regular places. My friend paid £50 for a 'bridal underskirt'. I found the same one on ebay for £10, delivered (and then borrowed hers for free!). An underskirt is an underskirt. If things are used in normal life, they can be purchased from normal places. If they are not used in normal life, question whether you really want them.
But mainly, enjoy. We had such a wonderful day surrounded by all those we love. It was so special to us, I'd do it again in a heartbeat if it were socially acceptable!