Trello uses boards to organize information and tasks so you can manage any project and see exactly what's getting done. The Trello app for Slack makes it easy to manage cards on your boards, change due dates, and attach conversations to cards — directly from Slack.
From the app page on the Trello website, select Add to Slack.
Choose a Trello team to link to Slack.
Click Add to Slack to the right of your team.
Click Allow to grant Trello access to Slack.
Note: If someone has already installed the Trello app to your workspace, you'll see Open in Slack on the app page.
Link your Slack account to Trello
From your desktop, click Apps at the top of your left sidebar. If you don't see this option, click More to find it.
Search for and select Trello to open a direct message with the app.
Click the lightning bolt icon to the left of the message field to open the shortcuts menu.
Search for and select /trello from the menu to add the slash command to the message field.
Send the message.
Click Link Trello Account.
Select Allow, then click Link Accounts.
Set up Trello in Slack
Once the Trello app is installed to your workspace and you've connected your account, you can link boards to channels. If at least one board has been linked to a channel, you can add new cards to the board from the channel.
Add the Trello bot to channels
From your desktop, open the channel you'd like to add the Trello bot to.
Click the lightning bolt icon to open the shortcuts menu.
Type /invite @trello into the search field at the top of the menu.
Click Send to message input.
Send your message to add the bot to the channel.
Link boards to channels
Click the lightning bolt icon to the left of the message field to open the shortcuts menu.
Search for and select /trello from the menu.
Following /trello in the message field, type link and the URL of the board you'd like to add.
Send your message, then click Link to Channel.
Add new Trello cards
Click the lightning bolt icon to the left of the message field to open the shortcuts menu.
Search for and select /trello from the menu.
Following /trello in the message field, type add and the name of the card you'd like to add.