You wouldn’t share your phone number with everyone you meet, or leave it on a Post-it note in a public phone box. So why wouldn’t you treat your email address with the same precaution?

Read on to find how to avoid making the most common mistakes that lead to spam emails peppering your inbox.

1) Sharing your email address with the world

Why it’s a mistake – Spammers get their contact lists from trawling the web, as well as buying them from marketing companies and service providers that share addresses for a fee. The more times your email address appears online, the more likely it is to be scavenged by spammers.

What to do instead – Never post your address on open forums or social networks – it makes life easy for the spammers, as they can use software to lift email addresses. Even when dealing with reputable companies, protect your real email address by creating alternative accounts to use when signing up for services.

For example, to create a free ‘alias’ account within Outlook.com, click on the cog icon then click options. Under Managing your account, click Create an Outlook.com alias. You may need to confirm your password.

You’ll see a screen saying Create a new email address and add it as an alias. Here, you can make up a new email address – it can be simple to use your existing one and add a number at the end. Untick the box saying Send new emails from this address by default, and tick the box to create a new folder for emails within your existing email account. Any emails sent to your alias address will now show in this sub-folder of your usual account, so you can check them if you need to.

2) Replying to spammers

Why it’s a mistake – Despite what the email promises, we’re willing to guarantee you haven’t actually won the Nigerian national lottery, so there’s no need to reply. Apart from risking a malware infection, replying to spam emails validates your address and advertises yourself to spammers.

What to do instead – Most webmail systems, such as Gmail or Hotmail, have a useful Report spam feature. In Gmail, for example, highlighting the message brings up buttons marked Delete and Spam, both of which remove the message from your inbox. Within a message, the button marked Reply by default also offers Report spam, which helps teach your email system which messages you don’t want.

3) Ignoring the small print

Why it’s a mistake – Many sites and services ask you if you want to receive news and offers from them, or from partners. There’s usually a tick box next to (potentially confusing) terms and conditions. The emails you receive might not technically be ‘spam’, since you agreed to receive them, but over time the messages from companies and various partners can become overwhelming.

What to do instead – Read the small print carefully when signing up for services. Carelessly clicking through alerts during registration can lead to irrelevant messages and unsubscribing from mailing lists later can be a pain.

4) Unsubscribing from spam the wrong way

Why it’s a mistake – Some spam messages include an option to unsubscribe – but in fact these links provide the spammers with ammunition. In the same way that replying to spam messages confirms your email address, using the ‘unsubscribe’ link can actually alert spammers to a valid email address, and also provides them with details of what email software you are using. Worse still, it could lead to a web page that’s been set up to infect visitors with malware or snooping software.

What to do instead – Use the Report spam or Report phishing options within our email system to help train the system and reduce the number of messages getting through to your inbox in future. From the Settings options in your email system, set up filters to send future messages from the same sender to your Spam folder.

5) Staying signed up to too many things

Why it’s a mistake – We all sign up for news services, customer promotions and price alerts that are pertinent at the time, but after that holiday has passed or purchase has been made we forget to unsubscribe from the mailing lists.

While the real definition of spam is that the messages are unsolicited, an unmanaged mountain of marketing messages can have the same effect on your inbox. The danger is that with so much no-longer-relevant clutter, it’s easy to miss important messages.

What to do instead – You can opt out of legitimate marketing messages by clicking on the email and looking for a button marked Unsubscribe or Remove me, which usually takes you to an external site where you can unsubscribe from further emails from that particular sender.

Only use this function if you are sure the email is from a reputable company, and make sure you click the option that completely removes you from the list and doesn’t merely limit emails.