Open Finder
Go to Applications
Find the app you want to delete
Drag the app to Trash
Enter your admin password if prompted
Empty Trash
Alternatively, right-click the app in Applications
Select Move to Trash
Empty Trash
To delete apps installed via the App Store
Open Launchpad
Click and hold the app icon until it jiggles
Click the X on the app icon
Click Delete
If prompted, confirm the deletion
To delete a downloaded installer or app package
Open Downloads in Finder
Move the installer file to Trash
Empty Trash