Read here how to store maidsafecoins:
tl;dr : It’s enough to withdraw the maidsafecoins to a bitcoin address for which you have the private keys…the security of the maidsafecoins will be that of a bitcoin address until you exchange them for safecoins.
Personally I used www.bitaddress.org to generate a paper wallet where I now keep my holdings.
[Edit: in Omniwallet you can import the private keys of you BTC address for when you want to send them to an exchange for example. You can also add your bitcoin address as watch-only in there]