My Macbook mouse keeps randomly disapearing.

Hello ivy36, 

Thanks for reaching out! I know when I lose track of the mouse cursor I find that the “Shake mouse pointer to locate” feature helps me quickly find it. With this feature the pointer will briefly get bigger so you can see it. All you have to do is shake the mouse or quickly move your finger on the trackpad. To turn it on, go to the Apple Menu > System Preferences > Accessibility> Display, there you’ll find a check box for “Shake mouse pointer to locate” in the bottom of the window. You can find out more about this feature under “Tip:” in the “Change the appearance of the desktop” section: Make it easier to see what’s on the screen of your Mac. 

Have a great day!