Connecting to Twitch IRC can be quite the task for those not knowledgeable with IRC client, check out how you can set yourself up connecting to Twitch chats using HexChat.
Adding a Network
Navigate to HexChat > Network List (or press ctrl+s)
Click Add to add a new network. Name it whatever you desire.
Double-click newserver/6667 and change it to read irc.twitch.tv/6667
Untick Use global user information (if it’s ticked) and enter your Twitch user name in the Nick name field and your OAUTH token in the Password field and click OK
Note - You may tick Connect to this network automatically to join twitch chat automatically when you start HexChat.
Now close the edit network window, select your newly created network and click Connect.
Standard IRC context applies here as above. To join a channel simply type /join #channelname in the dialogue box.
HexChat can be configured to join channels automatically as well. To do this simply right click an already joined channel and tick Autojoin.