First, download the telegram messaging up on the AppStore or PlayStore. Telegram is the most popular messaging app among English-speaking traders. The WeChat is popular too but those tends to cater to Chinese traders.

Telegram Groups

Whaleclub: The largest Bitcoin trading group at almost 3000 users. dabbles in some forex trading. This chat group is the most well-known and easiest to join, everyone and their grandma is in it. The quality of discussion is what you'd expect for a chatroom overcrowded with scrubs. Flibbr and BTCVIX founded the whaleclub brand a few years ago before falling out. I almost never check this channel.

Whalepool: This is also a channel started by Flibbr, apparently to get away from the overcrowded rabble in his original room. Some familiar faces here and popular traders, basically whaleclub but less bad.

The Coin Farm: The largest and most active altcoin-focused trading chat groups at almost 2000 users. A good place to hear breaking altcoin news before it hits twitter. Be prepared for politically incorrect banter, drunk rants, excessive trolling, and shills. Occasional discussion about prices and analysis. Founded by Drei4u in 2016, I think I'm a mod there or something.

Blockfolio: A chatroom started by Masternode, a well-known investor in the cryptocurrency scene. It started out as a place to discuss Blockfolio, one of the best altcoin trading apps. Naturally when you get that many altcoiners together they tend to stick around. Fairly strict moderation.

CryptoGroups: A group for finding those niche telegram groups focused on a single altcoin or whatever.