First of all make sure you have your .wim File on a Network Share. Then you can start SCCM and and add your .wim file.
Make a right click on your Folder where you want to import your image and then say "Add Operating System Image". Type in the UNC path to the Image. In this example the .wim file calls "W8EE64GRP".
After successfull import you can create a "Distribution Point". Click on the before imported image and create a new Distribution Point.
Select your Distribution Point.
Now we can create a Tast Sequence. In my case i have allredy a present Task Sequence. So i can Duplicate this one. If you haven't a Task Sequence you can create a new.
In the Task Sequence change the Image file and the unattend.xml if present.
The next step will be to create a new Collection.
Now we must connect our Image with the Collection. We must now create a new Software Distribution Point. Click on your folder where you want to add the Advertise Task Sequence. Attention: Select "Advertise Task Sequence" not New – Task Sequence.
Select the before created Task Sequence and the before created Collection. Also make sure you checked "Make this task sequence availible to boot media and PXE". If you forget this your PXE Boot will not work. You can save yourself much time if you check this now. 😉
You must create "Mandatory assigments". In my case i checked the three checkboxes all.
That should it be for now. You can now add a computer to your Collection and try to boot. Hopefully it will start your installation. 🙂