Separating bitcoin cash (and bitcoin gold) from original bitcoin

[mercian]

Hi,

I have an old (pre-fork) bitcoin on my computer and would like to realize the bitcoin cash and bitcoin gold it now represents.

How do I go about doing this? What is the correct procedure and what software/wallets are recommended?

The wallet I have the coin in (MultiBit) is no longer supported by KeepKey so I need to find another wallet.

Looking forward to hearing from you