Puttygen

Run the puttygen.exe if you do not have it you can download it here.

Here you can change the key type and length for this example we will use default. For more information on industry standards refer to this page.

Click Generate and follow the instructions of moving your mouse in the space till the bar is filled.

Once finished your public key will be displayed as well as some options to set a passphrase and save your keys. The box at the top is your public key that you would copy into your authorized_keys file in the ssh directory. 

Note when you save the private key its in format ".ppk"(Putty Private Key) this will only work in the putty client. If you need a private key without the putty format you can find it under Conversions.

Bitvise SSH Client

Instructions for Bitvise can be found here.