How many of these 7 Slack tips did you already know?

1. ARGH! Someone posted something on a channel and you don't remember when or where. Don't start clicking around and scrolling! Just type /search and then a few words that you recall about the posting. Slack will find all occurrences of your search word(s) in various channels. 
2. WHOOPS! Need to make a quick edit on your last post? Just press the UP ARROW and it will change the last post into "edit" mode. Super helpful for quick corrections.
3. D'OH! Did you forget something? Next time the minute you realize you need a reminder, type /remind and tell Slack what you need. You can use simple conversational phrases like "remind me on Wednesday at 9am to call Bill". Want to see all you're reminders? Type /remind list in any Slack channel. You can also choose to be reminded about a specific slack message just by clicking on "more actions"
4. SHOW DON'T TELL: Curious how your friends are able to post a clever response graphic so quickly? Type /giphy and a phrase to quickly pop up an amusing graphic. Not working? Here's how to install Giphy into your Slack account. There's GFYCAT, too!
5. RE-GIF'd: Too many memes making it hard to read the chat? Type /collapse and all the media in your Slack channel will be temporarily hidden. To revert back, type /expand  
6. PICS not CLICKS: You can add the perfect emoji to your response without lifting the mouse. Just type the colon key ":"  and then a description of the emoji you want.
7. KINDA BIZAY: Let people know your status by simply typing /status  and include a description of what you're doing. By default, this will reset each night so you don't have to remember to update it.

This shortcut summary from Inc magazine is really helpful too!

https://www.inc.com/business-insider/how-to-use-slack-like-a-pro.html