Always go to the main op shops, such as Salvos, Vinnie (slightly more expensive), Vincent De Pauls, Goodwill etc. The smaller ones tend to be boutique ($$).
The dodgy areas tend to have the most interesting stuff.
Go for good patterns, good quality materials and either classic or very weird cuts, nothing in the middle as it will just look frumpy.
If you thinks its a 'Maybe' its a 'No'
Always try on the clothes, too short legs or tops showing bra straps will NEVER be cool.
Signature items should be chosen carefully, thing to yourself, can I wear this to work? Uni? Out? Family?
Its best to go back a few decades, last season will always look like last season.
Absolute no-nos
NEVER buy matching sets (separate them if you have to)
Never buy shoes (unless your very brave)
Shoulder pads, pleats in pants and box suits went out and should stay out
- Mod
Tips:
Jewellery can be great but careful what decade you team it with
Scarfs and odd sorts can be found in the boxes and baskets around the counters, don't be afraid to dig around (think silk scarfs and Burberry knits)
Funky prints and memorabilia can not only be cool but actually be worth something (think Kermit the frog T-shirts, original McDonalds uniforms, collectors items!)
Free Cycle - a site for people to give away stuff they no longer want/need to those who might want/need it.
Goodwill Industries Charity Stores - selling goods to people at a reasonable price to provide "a hand up, not a hand out" or "a chance, not a charity".
Salvation Army Stores - selling goods to create funds to use for assistance for those in need.