Criminals aren’t always thugs with meaty arms and little between the ears. In our ever more interconnected world, these days many thieves wear suits, have charm, act in a sophisticated manner and make out they are on our side.

Sadly I’ve been engaged in this world personally, as my image has been used across social media and online advertising, to try and dupe vulnerable people. I’m fighting it as hard as I can. Yet as these con artists get more professional we all need to get more vigilant. Here’s my six scam self-defence rules…

1.Never give personal details if they text or email. Fraudsters commonly send messages asking for your details to break into your accounts, claiming to be from a bank, insurer, HMRC, or even the police. This falls into two camps.

a) Phishing (a geek spelling of fishing): This a scam email, purporting to be from a company it hopes you have a connection with e.g. your bank saying something like: "Your bank security is broken, click here" or, "You’re due an HMRC tax rebate.”

It’ll then take you through to a professional-looking website – often a mirror image of the real thing, and it’ll ask you to put in your password or personal details in.

Never click a link in an unexpected email or open an attachment unless you're 100% sure of its contents.

b) Smishing (ie SMS-phishing). Like phishing but by text not email. Yet what’s tricky here is deciding whether it is just spam or a scam. If it is spam – a legit company sending annoying sales pitches - it should allow you to text back to stop future messages (more help on stopping spam texts, phone calls and door knockers at www.moneysavingexpert.com/stopspam).

Yet if it is a scammer, texting back isn’t a good idea as you’re just validating that it has texted a legit phone number so you could get more – and of course never call them. If unsure play safe and delete it.

2. Beware fake dialling tones when you call them back. Vishing (voice phishing over the phone) is a growing issue. Calls can pretend to be from banks, insurers, police, utility providers etc, all asking for passwords or personal details. Don’t do it.

They could even purport to be scam protection calls with patter such as: “There are lots of untrustworthy people out there, we need to call to protect you, it’s a horrid world.”

So, if it’s an unexpected call ALWAYS say you’ll call them back. If it is legit it won’t mind. And don’t call on the number it gave you - go and find that institution’s official number.

Even that may not be protection enough though. An increasingly common trick is where they call, and tell you to call back. However when you hang up, they don’t, and instead just play a dialling tone, tricking you into thinking it’s a new call, but they answer.

If you’ve any suspicions, then as well as finding the right number to call back, either a) Call from another phone b) If using the same phone, call a friend first, if ‘the bank’ answers you know they’ve spoofed a dial tone c) Wait a decent time before calling.

3. Know the scammers’ tells. In poker a ‘tell’ is how you judge when someone is bluffing. Similar tells applies to cold calls from scammers, including…

- Anyone rushing you, you never need to make a decision straight away.

- Anyone asking you to pay in an unusual way (such as vouchers).

- Poor grammar or dodgy spelling in emails, or starting emails with “dear sir or madam”.

- If someone you’ve never met asks you to send money.

- Job adverts that ask for money in advance.

- Unsolicited calls to help you fix your computer (genuine computer firms don’t do that) and generally I’m not in favour of any cold calling anyway, even if legit.

- Facebook ads for crypto currencies. It has banned those ads, so if they get through they’re not legit.

4. Don't fall for fake deals on WhatsApp & Facebook and other social media. Many bogus offers popping up in people's feeds and messages, eg, Alton Towers and Ryanair giving away free tickets on WhatsApp.

The key here is to know the source. Is the person giving you the information trustworthy, and are you certain it really is that person. Go to where you know it’s legit, and look for the same offer.

It’s easy to use lookalike web links, so if you think you’re reading an article from The Times or The Mirror or even my MoneySavingExpert.com – think about whether you went direct or clicked a link. If the latter it may be a spoof from a clicked link in an email which looks similar.

As you may know I’m in the midst of a campaigning lawsuit against Facebook which has published over 1,000 scam ads with my pic in. None are genuine. I’ve said it before, and I’ll say it again I DON’T DO ADS! So any ad with me in is a lie.

5. Ensure you've antivirus software installed on your computer. Free software which, while not as full of features as paid-for programs, still keeps on top of threats. These include Windows Defender, Microsoft Security Essentials and Avast Antivirus free (full comparison in www.moneysavingexpert.com/freeantivirus). Remember to update these regularly and ensure your firewall settings are on and set to a high-enough security level.

6. The safest way to pay is via credit or debit card. Credit cards are covered by the Section 75 law which means if goods cost £100 to £30,000 then the card firms is jointly responsible. For debit cards there’s the slightly less powerful Visa, MasterCard and Amex chargeback rules. So pay on plastic and if it’s a scam you can try to get your money back through the card firm. Pay by bank transfer, cash, cheque, or vouchers and there’s little protection.

For more help on how to find out if you’ve been scammed previously, and what to do if you have see www.moneysavingexpert.com/stopscams.