I will show you how to make a 9v battery flashlight. This is a list of things you will need:
1x LED (Any color. I used yellow.)
1x switch or button
1x 9v battery
The first thing that you will do once you have all of the materials is: bend the LEDs leads so it touches the switch and the positive contact on the battery. If you're not very experienced with electronics the longer lead on the LED is the positive lead.
Step 1: LED and resistor line up
I used a 62 ohm resistor for a 2.4v LED but the battery was only at about 6.5v.