There's not much to say here but that these are absolutely random tips that will help you find the best items when you're doing your thrifting.
Let other people do the work for you.
Contrary to when you shop at a regular retail clothing store you actually want to try and grab what others have tried on. At a thrift store people are picking through all of the items to find the best items and chances are someone else has already touched what you want. A great idea when thrifting is to go straight to the dressing room area if there is one and check out the stuff that's been left outside. It's probably some of the best stuff you can find. Maybe it didn't fit the person before you but it doesn't mean you won't look great in it.
Don't go in looking for something specific.
It can be hard to find that blue polka dot dress in a size 10 if that's what you're looking for at a thrift store. However, you can definitely find a great dress for your cocktail party. The best things at the thrift store are found when you are simply looking for something you like. You can be so specific that you miss out on that perfect item in the other isle. Try thrifting when you have nothing better to do. The extra time and ease will help uncover hidden gems.
Shop out of season
Just like in retail, thrift stores will have sales at the end of seasons. Also, because we work in a huge amounts of inventory we jump on the opportunity to get rid of a coat in the summer time to make room for other items. You will actually have much better luck haggling with a thrift store owner for something that is not currently in season. Next time you're in the store during the winter grab a sundress or a tank top and ask them for a discount.
Keep checking out the Thrift Blog for more tips and tricks regarding thrift store shopping.