If it doesn't use PayPal and it wants you to use a credit card and/or western union, definitely a no for me. But I usually do my research and get the reviews about it first. And I think you just tell by instincts that a certain site is not legit.
I always check for customer reviews. Also, I make sure that I only buy stuffs from trusted sellers or big online sellers. I also pay only thru Paypal. So just in case they turn out to be a bogus one, I can open a dispute thru Paypal and get my money back.
If they have been in the industry for years and have established a name already like Amazon and Ebay then it's legit. I'd advise to stick to those online shops anyway so you won't end up being ripped off or losing your money. There's a lot of scams online so it's best to be careful.
I love online shopping but if I am not sure about the store if it is legit or not , I prefer to choose cash on delivery option at the time of check out or else if I am purchasing something from international website I google the site and see all the reviews and complaints of the customer about that site.After satisfaction I order from that site.
