When trying to play louder, many students make the mistake of just strumming faster or increasing the length of their strum. Peter Vogl has a quick tip that will show you how to create more volume from your guitar.
The more pressure you place on the strings, the more volume you are going to get. Pressing down on the strings and slightly towards the guitar will help you create more power. Being able to create more volume is a fundamental technique that will help add dynamics to your playing.