For everyone who can’t remember shortcuts, I highly recommend CheatSheet by Media Atelier. It’s a nifty little program that runs in the background on your computer. When you’re in any app and you can’t remember how to do something, press and hold the cmd ⌘ key, and a sheet will come up telling you what shortcuts are set in the active app. This is often quicker than finding the right menu in the toolbar, I find this little program invaluable.
E.g. this is what it looks like for me this morning while I’m in Safari typing to you:
The sheet only remains visible while you hold down the cmd key, so as soon as you either press the keys you need, or release the cmd key, it disappears and you carry on with your task.