The Litecoin wallet is very similar to the bitcoin wallet. When you down and install the software it essentially creates a default wallet.dat file. Think of this as the ID to the bitcoin or litecoin network for your wallet. You should also encypt any wallet you use right away. If you are asking how to create multiple wallets, you would need to create those by creating a new wallet.dat file. The best thing to do for multiple wallets as far as simplicity is concerned is to probably use multibit which handles multiple wallets from within the wallet software itself.