Here is how a miner can get set up to accept storage deals. The first step is to install a Lotus node and sync to the top of the chain.
lotus-storage-miner set-price <price>
This command will set up your miner to accept deal proposals that meet the input price. The price is inputted in FIL per GiB per epoch, and the default is 0.0000000005.
Clients need to be able to find you in order to make storage deals with you. While there isn't necessarily anything you need to do to become discoverable, here are some things you can try to check that people can connect to you.
To start off, make sure you are connected to at least some peers, and your port is open and working.
If you are in contact with someone else running Lotus, you can ask them to try connecting to your node. To do so, provide them your peer ID, which you can get by running
lotus net id on your node.
They can then try running
lotus net findpeer <peerID> to get your address(es), and can then run
lotus net connect <address> to connect to you. If successful, your node will now appear on their peers list (run
lotus net peers to check).
You can also check this by running a second instance of Lotus yourself.
A client should be able to find your ask by running
lotus client query-ask <minerID>. If someone is not able to retrieve your ask by doing so, then there is an issue with your node.