This step-by-step guide will help you to familiarize yourself with the Slack platform, specifically how to add a custom emoji to Slack's preexisting emoji library. After following this process, you should develop an understanding of how to add and use your own emojis to make using Slack more fun and interactive for you and your team.
1. Open Slack in your browser or via the desktop application
2. Click the emoji icon positioned below the text box
3. Click "Add Emoji"
4. Click "Upload Image" and select the image you'd like to use for your custom emoji
Square images under 128KB and with transparent backgrounds are preferred. If your image is over 128KB, Slack will try to resize it for you.
5. Type in a name for your custom emoji
The name you choose for your custom emoji must not be the name of an existing emoji.
6. Click "Save"
7. Wait for the notification that your custom emoji has been added and is ready for use
8. Use your custom emoji by clicking the emoji icon below the text box
9. Type in the name you chose for your custom emoji
10. Select your custom emoji