How to add multiple ssh keys for multiple github accounts on a single machine

file.sh

ssh-keygen -t rsa -b 4096 -C "aash.discover@gmail.com"

## when prompted for file name, take id_rsa_personal

ssh-keygen -t rsa -b 4096 -C "aash@workmail.com"

# when prompted for file name, take id_rsa_work

## below are the content of ~/.ssh/config

Host personalid.github.com
  Hostname github.com
  PreferredAuthentications publickey
  IdentityFile /Users/aash/.ssh/id_rsa_personal
Host workid.github.com
  Hostname github.com
  PreferredAuthentications publickey
  IdentityFile /Users/aash/.ssh/id_rsa_work