There are hundreds of websites out there saying that they can make you money. Some are genuine. They really do give good advice on how you can make a bit of extra cash on the internet. But many – maybe even most – are scams.

Pretty much everyone hates scammers. You might have a reason yourself – have you ever lost money to one? Legitimate affiliate marketers hate them because of the suspicion and mistrust they cause, therefore making it more difficult for affiliate marketers to sell their products as no one believes what they say! The only way to stamp them out is to starve them of what they want: your money.

But how do you spot a scam? It can be very difficult. The best scammers, the ones that make the most money, are identical in appearance to legitimate sellers. But most aren't that good. Most can't be bothered. Scammers, after all, are lazy. They can't be bothered to make a living honestly, so they do it by cheating instead.

And while it's probably impossible to stay completely safe (there is always an element of risk when you buy something, after all, online or off), there are some things you should look for when visiting a website. It will take a little extra time, but it might well save you money.

The first thing to always, always check is contact information. Is there any? If not, run! A genuine seller will want you to be able to contact them – after all, you might want to offer them more money! Or you might have a question you want to ask about their product before you buy. Genuine sellers will be happy to answer – scammers just want to hide.

If there is contact information, look at the e-mail address. Is it free? There's nothing wrong with that by itself, but remember how easy Yahoo and Hotmail accounts are to set up. They're also more likely to be blocked by spam filters. A paid-for e-mail address means a higher chance this person is legitimate.

Second, check the small print. Is there a disclaimer? Genuine sellers realise that their product will not be able to help everybody – no product can – and that there is a chance you'll be disappointed. As such, they'll add a disclaimer saying so. They'll also have a money-back guarantee. Of course, the words 'money-back guarantee' are no guarantee of anything - typing something doesn't make it true, and the words alone don't mean you'll get your money back. But they're a step in the right direction.

Third, have a quick exploration of the site. What other websites does it link to? Reputable sites won't be happy about scammers linking to them – and scammers probably won't want to let reputable sites know they exist. After all, if the wrong person finds out the scammer could find themselves in court - much of what they do is against the law. Scam websites tend to be small – often just one page. Genuine websites have more content, and therefore more pages. A small website isn't proof that you're being scammed – but it should make you wary.

A final thing to check, and this is one of the main things that gives scam sites away, is the testimonials. They're supposed to reassure you, convince you that the product is worth buying. You can use them you work out whether you're being scammed or not. Read them carefully. Do they sound natural, like something you might write? Or do they sound like a continuation of the sales pitch? The second is a sign they're probably trying to scam you. Also look at their photographs – and this goes for all the photographs on a site. Do they look professional, like they could belong in a catalogue? Or do they look like ordinary snapshots? The more professional they look, the more likely they are to be fake.

It is possible to avoid the vast majority of scammers. You have to be careful, take your time when reading a website, and not rush into anything. Don't get carried away by a sales pitch! If they're genuine, they'll still be there tomorrow – and still at the same price, whatever they might say!

The only way to defeat scammers is by preventing them from making a profit. So, when you next visit a site that promises to make you money, be careful - don't pay them unless you're sure!