Use fdisk /dev/hda ->To create new partition.
Type n-> For New partition
It will ask for Logical or Primary Partitions. Press l for logical.
It will ask for the Starting Cylinder: Use the Default by pressing Enter Key.
Type the Size: +100M ->You can Specify either Last cylinder of Size here.
Press P to verify the partitions lists and remember the partitions name. Default System ID is 83 that means Linux Native.
Type t to change the System ID of partition.
Type Partition Number
Type 82 that means Linux Swap.
Press w to write on partitions table.
Either Reboot or use partprobe command.
mkswap /dev/hda? ->To create Swap File system on partition.
swapon /dev/hda? ->To enable the Swap space from partition.
free -m ->Verify Either Swap is enabled or not.
vi /etc/fstab/dev/hda? swap swap defaults 0 0
Reboot the System and verify that swap is automatically enabled or not.