If you are reading this guide and you know nothing about Sitecore, then I would recommend reading the first part of this article http://jondjones.com/learn-sitecore-cms/sitecore-developers-guide/sitecore-getting-with-sitecore-development/how-to-install-sitecore-7-for-beginners/. As long as you have a valid Sitecore license and the Sitecore 8 installer, then we are good to go. When you run the installer, the first screen you will see is the welcome screen, skip past that

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Agree to the T&C's sitecore_8_installation_2

Select your install type. For a brand new build you want to select 'Complete':

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Add your license file:

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Add your SQL server details:

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Add the destination where you want to install Sitecore

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Add the ISS hostname. The installer will also add an entry in your host file

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Then sit back and relax.

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When the installer has finished doing its thing, your new Sitecore 8 website should load.

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Sitecore 8 looks a lot different than version 7. By default, you can log in with the user name 'Admin' and the password 'b'.