11 Oct 2018
To be clear, v8 is not finished yet, it is still in Alpha state as far as I know, but you can check it out and have a play with it yourself if you are interested.
Recently I have been looking into Umbraco v8, to be nosy and also to see if I can contribute. You may have thought about checking it out yourself but you might have stumbled at some of the hurdles.
First of all make sure you have installed the latest windows updates, you have the latest version of .NET Framework 4.7.2 developer pack installed and your version of Visual Studio is 15.7 or higher. More details about getting your machine ready here.
After you have done that, the next thing you need to do is check it out in GitHub.
You can easily get into a mess with this so I wanted to give you some steps to check it out properly, even if you've already checked out the dev-v7 branch.
Fork the Umbraco-CMS project in GitHub if you haven't already.
Clone your repository like this, notice it has prjseal in the url, you will need to swap it for yours.:
git clone https://github.com/prjseal/Umbraco-CMS.git
You should be on the dev-v7 branch at the moment. This is the default branch. We don't want this one, we want temp8.
Before we switch branches, set the umbraco repository as the upstream. This will help with keeping your fork up to date.
git remote add upstream https://github.com/umbraco/Umbraco-CMS.git
Now you want to fetch from the upstream repository using this command
git fetch upstream
Checkout the temp8 branch locally
git checkout -b temp8 origin/temp8
Now you have the temp8 branch on your machine but it could still have some leftovers from the dev-v7 branch, so in File Explorer in your Umbraco-CMS folder, delete all files and folders, except your .git and .github folders.
Now you need to get a clean copy of the temp8 branch
git reset --hard upstream/temp8
Push those changes up to your fork
You should be all set now. You can open the Visual Studio solution file in the src folder called umbraco.sln
Rebuild the solution. It should take a while, as it downloads and installs all of the pacakges from bower and nuget.
Run the website project, you will go through the usual Umbraco installer.
Congratulations you are now running Umbraco v8!
If you would like to see what v8 looks like you can watch this video I made: