If you want to create an event that is very like one you have already created (on the same dates for example), there is a feature called "add another one like this". Find the event you want to copy and click on Edit. At the top of the screen on the left, you will see the button "Add another like this".
All of the event details will have been copied across. The bookings are not copied across.
Make any changes you need and then save. Warning: The published box will not be ticked for the new event, so if you want it to be published, you need to tick it before you save.
When you publish the event, the webpage address for the new event will automatically be created using the name you have given the new event. If it's the same as the old event, it adds -1 on the end.
Click here for details on how to change the url (webpage address) for an event, after it's been created.