Eric KJ4YZI has a great YouTube channel and he is starting a new series...
"This is where you start. Video #1. I have done a quick video on each one of the HF bands to educate the newcomer to the hobby or for anyone who wants to learn. You can learn here about each one of the bands we have, such as when you can operate these bands, how long a wire antenna for that band should be and what you might find when exploring each band. I hope everyone who watches this that may be new to the hobby will learn from this. PLEASE comment below, give a THUMBS UP for the effort of these videos, subscribe and stay tuned for each new video released."