shrinking partition so i can add another OS

[TheConsaw]

hi guys, new to linux so forgive my n00bness
so i recently installed sabayon 4.1G and have now successfully updated to 4.2,
thing is i allowed sabayon take up all the available space i had on the laptop
now i want to install another distro
i have found gparted, but i cant seem to figure how to shrink sabayon partition, it wont let me do anything, only offering me the delete option
i have an idea on what i want to achieve, as i can do this in vista blindfolded, but this linux world is new to me !
any help appreciated thanks

[Stupot]

If I recall correctly, you can't resize a partition that you currently have mounted. So, if you want to use Gparted, boot up the LiveDVD and use the GParted on there to resize the partitions on your HDD.