In the video above I answer common questions like "how to get even sounding strums" and "how to strum the right strings for each chord".
The video above shows you how to strum correctly with a plectrum.
The important part of strumming is being effective and relaxed. These 2 videos give you advice on this. It doesn't matter if you play with a pick or not. It's your choice, use whatever feels most natural to you.
The video above shows you how to strum correctly using your thumb and fingers.