Usually, you may don’t want to change anything about your mouse cursor. But if the size of the cursor is worrying you in anyway then there’s a way to increase cursor size in Ubuntu. Follow the steps given below.
Firstly, go to Settings.
Choose Universal Access option from the left pane. There you can see the Cursor Size option set as default.
Clicking on the Cursor Size option will popup a window as given in the following screenshot. Then you can choose the preferred cursor size.
I hope this Ubuntu tutorial to change the size of your cursor will be helpful for you.