Before Starting any of these steps you want to first set up a Website Using SQL servers
(if you dont know how to do this go read my blog on "How to install Umbraco 8 using SQL Servers" Link Below)
So now you have Umbraco 8 set up with SQL Servers We can get started.
Step 1. So assuming you now have a website in you visual studio you can run and it all works. Now you need to add a class library. ( Right click on you solution and click "Add" then "New Project" Select "C# Class library (.NET Framework)" Name your new project Website.Core
Step 2. Now you have your class library created you will need to add a new class under your New Class Library. To do this right click on your Website.core project folder then Click (Add>Class>Blank Class) and name your new Class "ModelsBuilder.cs".
Step 3. Next Its time to set up your custom tool. Right Click on your new class "ModelsBuilder.cs" and click "properties". Type " UmbracoModelsBuilder " to the right of where it says Custom Tool. Now Click "Tools" from your Visual Studio Top Menu and Select options. Scroll through the options until you see Umbraco and click on Umbraco.
Fill out your site URL ( The user name and password is how you sign into your Umbraco 8 back office.) And click OK.
Step 4. Now you need to make sure your web config file is set up properly. Click on your Website.Web Project and to the bottom you should see Web.config open this file in your Visual Studio Viewer. In the app setting sections make sure the 3 ModelsBuilder setting Read the following.
<add key="Umbraco.ModelsBuilder.Enable" value="true" />
<add key="Umbraco.ModelsBuilder.ModelsMode" value="Nothing" />
<add key="Umbraco.ModelsBuilder.EnableApi" value="true" />
Step 5. Next you need to upload your nugget packages to install the models builder. Click Tools>Nuget package manager>Nuget Console and then in the console next to PM> Type out the code below
/* only one at at time*/
/*you also need to install*/
" **Be Sure To Install On Both .WEB and .CORE Projects**
Step 6. Now your NuGet Packages are installed. You want to try run your Custom Tool on your Models Builder Class.
To do this Right click on your ModelsBuilder.cs Class and select Run custom Tool if you have followed along correctly so far it should generate some folders for you containing your Umbraco Models.
Step 7. As long as you have have all your folders generated now you will need to reference Umbraco.Web in your .Core project.
Step 8.Next you want to save everything and Rebuild your site. After rebuild Click Run and If you have Followed along correctly your website should be working as usual.
Tip: if your website is not running as usual you may need to change the page references and the top of each of your views pages.
From: @inherits UmbracoViewPage<Contact>
To: @inherits UmbracoViewPage<Website.Core.Contact>
This will be needed to be done all all your views pages.