With /boot created, select the unallocated space, then click the Create button to create the swap space.
Again, we want to create a standard partition. Create.
For this test installation, 2000 MB, or 2 GB, has been allocated to swap, and that should be sufficient for most systems. OK to continue.
Now that /boot and swap have been created, select the remaining free space to create the btrfs-formatted root partition.
Once more,, we want to create a standard partition. Create.
For Mount Point, select /, and btrfs for File System Type. If you intend to use all the unallocated space, click on the radio button next to Fill to maximum allowable size. OK.
All the partitions have been created, click Next to continue with the rest of the installation.