Create and use a temporary email address.

Yahoo and Hotmail provide this feature in order to keep your private email address strictly for your friends and family members and only. The secondary address, you can use for your subscriptions and other purposes. If your secondary address is abused from spammers and your inbox is filled with spam messages, then you can delete it and create another secondary email address.

Use the Spam arrest service.

When you signup for Spam Arrest, you will receive a spamarrest.com email address. You can also protect your existing email accounts by forwarding them to your Spam Arrest email address, or by having Spam Arrest periodically poll them. In that way over 90% of your spam messages will be filtered.

Use your e-mail's filters.

Almost all email applications have this feature. You can create filters blocking spam words like "make money, opportunities, Viagra, e.t.c" .Doing that, you will block many of your spam messages but not all of them.

NEVER post your email.

Don't post your email on forums, websites, message boards, guest books and other online places. You should also avoid posting your contact email address on your website. Spammers use software robots and extract email addresses from thousands of websites. If you want to display your email at your website change it to jpeg photo with Photoshop or other image design software.

The use of email blocking tools.

Yahoo for instance has this excellent tool which can block up to 500 email addresses (the Free option, the paid one provide more) and this amount of spam emails will never reach your mailbox. Other web mail services provide similar features too.

The preinstalled filter in your email application.

If you use outlook express you can click "message" (from windows 98 versions and later) and then click "Block sender". Just doing that you will block many of your unsolicited emails.

Do Not respond to spam at all costs.

When you receive a spam message which asks you to click a link for whatever reason (fake unsubscribe and other) do not click it. If you do that, the spammers will now instantly that they deal with a real email address.

Do Not Ever open unknown messages with attachments.

This is critical. Most of the times the attachment will be a virus (especially if it's exe or zip format) If you open it you will activate the virus it contains and harm your computer. Accept email attachments ONLY from well known resources such as friends, business colleagues e.t.c. You should also have installed an antivirus which scans your emails before they are saved into your hard drive.