RPC is a method of communication between various crypto wallet interfaces like MetaMask, Mist, or MyEtherWallet and a given blockchain. Let's see how to connect some of these tools with Lisinski.
Almost every interface you want to connect to a special Ethereum network has the same input fields: name of the node, address, and port. Other information is usually optional. Let's connect MyCrypto, MyEtherWallet, and MetaMask to Lisinski.
MyCrypto
If you haven't already, please download the MyCrypto app.
Pick "Change Network" in the left menu, then scroll to the bottom and pick "Add Custom Node". In the popup which appears enter the data as follows:

After saving, you can start using the network as if with the Ethereum mainnet - it's all the same.
MetaMask
Download MetaMask if you haven't yet. MetaMask has an extremely simple interface for adding a new network - a single field for a node address.

MyEtherWallet
Finally, let's enter Lisinski manually into MEW. It's important to note that if you connect MetaMask to MEW, MEW will take its network settings form MM and you won't need to manually add the network.

You are now connected to Lisinski - go use it!