i'm not really sure what you are saying, but I use cfdisk to start off with to use it to chop up my drive to how I want it. 14.2 I am assuming is Slackware 14.2.
the menu on how to use cfdisk is on the bottom of the screen. delete new write exit etc..
when creating a new partition select new then back off what it is telling you in size then add whatever you want 3GB or 3MB the abbreviations for size are easily taken then used to give the sizes, you will not always get 3GB exactly due to how it needs to select the area in the HDD if it is smaller then you want just make it bigger.
3.2GB
nothing is written to the disk until you tell it to. so you can redo it time and time again until you get it to how you want it then select write
do not forget a swap partition as Slack will ask you where it is if you do not have one created.
my swap is just a 16GB SD Card in my slot on my laptop.
