Tips

Using language injection to work with Regex.

Use Live Templates to auto-complete common code structures for you.

IntelliJ IDEA can help create code for you saving your fingers.

You can view a wealth of information about your code in the scrollbars.

Quickly navigate around your recent files & locations to stay in your current working context.

Using the Problems tool window to find and fix errors as they occur.

Finding the parameter type can be really helpful for understanding your code.

View information about your code by looking at the gutter icons.

Git tool window

Use the debugger to help you understand what your code is doing.

Visualize the flow of data through a Java stream.

Structural Search and Replace is very helpful for finding exactly what you need in your project.