First, make sure you have EV3 software from LEGO.

Once you have it launched up, go to Tools and select Firmware Update.

Next to Online Updates, click Check.

Then, click Browse.

Select the firmware and then click Open.

Connect (via USB) your LEGO creation.

Under Firmware, click Download.

Watch the progress.

Once it’s done, you’ll see a message on your computer and also the LEGO creation you made will make an audible beep noise.