The first thing you have to do in HexChat is pick your username and the IRC server that you're going connect to. You can choose up to two more nicknames in case yours is already taken. This helps to avoid wasting time right from the beginning. Once you're connected, you can chat as normal in the different channels available.
The best thing about HexChat is that not only can you connect to a single network with the client; you can also chat on multiple servers simultaneously. The minimalist interface of this program makes it possible to converse on several networks simultaneously from the panel found on the left. Here you'll find a breakdown of the different networks, channels, and private messages you have.
HexChat is an excellent program for easily using IRC. It's an open source client that offers different customization tools for changing the colors of the interface and supports different programming languages for users who want to explore all its possibilities.