Step 1

In windows go to system management –> disk management, select the drive you have windows 8 on , then right click shrink and make space for Ubuntu from the menu (more than 10gb).

See here http://windows.microsoft.com/en-au/windows/repartition-hard-disk#1TC=windows-7

Step 2

Shut-down then boot into the Ubuntu live.

Step 3

when you get to installation type say “something else”.

Step 4

Then create a ext4 partition in the free space you made in windows and set it to “/” and “format”

you should also partition off some space (same as the amount of ram you have, or more if you want hibernation) and set this as “swap”

Step 5

Then set the 100mb “UEFI” partition (if you have one) to boot but don’t format it.

Click next and it should continue installation.