I've written this based on my experience of Bananian which is Debian based.

Deleting Swap File

swapoff /swapfile1

rm -f /swapfile1

Creating Swap File

The parition needs to be created as a swapfile and not ext3, ext4 or something else.

mktemp /dev/sda1

Create a file of 1GB

dd if=/dev/zero of=/swapfile1 bs=512 count=2048
chmod 600 /swapfile1
mkswap /swapfile1
swapon /swapfile1

vi /etc/fstab

Add an entry or change the existing one

/dev/sda1 swap swap defaults 0 0

or

/swapfile1 swap swap defaults 0 0

vi /etc/sysctl.conf

vm.swappiness Values

Value	Strategy
0	The kernel will swap only to avoid an out of memory condition, when free memory will be below vm.min_free_kbytes limit. See the "VM Sysctl documentation".
1	Kernel version 3.5 and over, as well as Red Hat kernel version 2.6.32-303 and over: Minimum amount of swapping without disabling it entirely.
10	This value is sometimes recommended to improve performance when sufficient memory exists in a system.
60	The default value.
100	The kernel will swap aggressively.

After reboot check current value

cat /proc/sys/vm/swappiness