It’s always a good idea to have at least two partitions, one for your O.S. and one for your data. There are a lot of programs which you can use to part your harddrive  (e.g.: [ gparted | qparted ]).

I’m pretty happy with my current schema, which I developed long time ago, when my harddrive was only 40 Gb. I wrote about this in this old post, which I’m translating from Italian to English.

This is a schema for an old laptop of 40 Gb, but you can extend the concept.

Harddisk: 40 Gb

/ 10 Gb (root, where you will install the operative system)

swap 1Gb (should be the same amount of RAM you’ve got if you want to suspend)

/home 29 Gb

The main idea is to create a 10Gb for your O.S., the swap for the RAM and then everything left should go as space for the home.

This is pretty good way to part your disk because:

  1. Your data are detached from the O.S., so you can clean your partition very quickly and put a shiny new one in no time.
  2. 10 Gb is maybe too many for the O.S., but I tend to install a huge amount of stuff and sometimes when writing big file you need space in tmp.

So far it works for me.

With my new (3 years old…) laptop I have this figures:

 

18.4 Gb for the root (/)

4 Gb for the swap

87.7 Gb for the /home