how did u know that a website of online-store is safe?

Now people aways buy something from a online store, like shoes, bags,clothing etc. We first start a explorer and type google.com, then  we will enter some keywords to search, for eg. i enter red wing boots , will get millions search results. So, which one should we trust?

The first result should be the offical site of red wing shoes, whithout doublt we can trust it, but u will find that we cannot buy a pair of red wing shoes from this site, the site only have the pictures of his products and tell us where can we buy them, if besides your home their is just a store nearby, u can buy it, but if u are far from, u should buy it from an online-store.

Their are lots of offer from china, but they are not authorized, Should we trust them? The answer is make careful and wise choice. Then u can do what i write below:
1. search from google.com or use a safe explorer like firefox and chrome, if the site is scame, the explorer will warming u.
2. Check this site whith a safty check site u know.
3. Read the return proxy and if their have customer service or email, then check this email in google.com whether their have complains.
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more ways? please send me an email:idoservice@hotmail.com

About the aurthor:
I have an online store that sales the replica designer handbags, if u want to buy one, why not contact me to see whether i have the one u want to buy? any questions u can send me an email.