Don't charge it! Buy only what you can afford.
Make a budget and stay with it. Shop early; you can often get great sales and deals just by shopping throughout the year instead of waiting til November! And scour your newspapers, online sites, etc. for coupons and sales!
I never leave the house without a list. That way I'm less likely to get sidetracked by impulse buys.
If you shop online, go through a site that gives you cash back for your purchase.
Wait for a sale! When I have cash in my hand I want to go crazy and buy, buy , buy. I have had to train myself to hold off on an item till it's one sale or to find it online and use a coupon to get it for less. Time is now limited but we still have a few weeks and there are a few items I am holding off on till the go down so more.
Start early and do your research to find the best prices!
Gift receipts for returns.
I recommend shopping online to avoid crowds and aggravation--but it's best to only use sites that offer free shipping, so you're not wasting money on that. There are usually lots of promotions around the holidays.
Make a list, check it daily with the 'new' sales on the internet.. Price-match when you can!
Shop close-out stores where you can get really nice quality gifts for really low prices. Close-outs I prefer are TJ Maxx, Ross Dress for Less, Burlington Coat Factory (nice home decor and glassware, unique toys), and Marshalls.
I shop throughout the year. No pressure that way. I can watch for amazing deals and find the perfect gift...come the holiday season , I can just relax and enjoy!
My top tip is to make a list and stick to it!