In Postmypost, go to the "Accounts" section and click "Connect".
In the pop-up window with a list of social networks, click "Connect" next to Discord.
Enter the address of the desired channel in the format
https://discord.gg/1504495329729446080, where
1504495329729446080 is the channel ID. Then enter the bot token and click "Connect".
After successful connection, you will automatically return to Postmypost, where a list of available channels for connection will open. Check the desired ones and click "Connect".