Just have fun with this thing. It's awesome. It gets some great sounds.
I haven't had the hd500 for the longest time, but the second I got it, I was going through the threads on here harcore. I spent hours studying meambobo's high gain guide. I dug deep into all the threads discussing the 4 cable method. I paid extra close attention to everyone talking about how important it is to change the 2nd input to Variax. Then I found all the threads where people were saying just to keep the 2nd input as same. Then I started getting into the threads talking about some clean patches having volume problems, and needing to make sure to get a clean boost after the mixer.....
Honestly, I was almost paralyzed worrying that I was going to do the right things to make my tone sound good. So when I got in there and started tweaking, I completely ignored the fun factor, and just spent hours nervously adjusting every setting and referencing back to the guides and foums to make sure I was doing everything right.
That changed last night though . I closed my browser, closed the manual, opened a new blank patch, went through a couple of amps until I found one I wanted, then just started jamming. To start, I didn't change the cab, I didn't change any of the tone settings, just played, and enjoyed it. As I went along, I reached down and started making some adjustments here and there. Then I tossed on a gate. A few minutes later I grabbed an EQ. Felt like I wanted a phaser on there, so I loaded a couple up and found the one I liked. Then I wanted to get it sounding weird, so I went to the Particle Verb. The final result is not a perfect tone. There might be some clipping somewhere in the chain. It might be extra noisy due to me using the wrong order. But damn, it was fun, and it sounds good to my ears.
All the information that has been put on these boards is great. Meambobo's guide is ridiculously informative, and that guy is a freakin' saint for putting all of that down for us to read. But don't let yourself get caught up in all that right away. There is plenty of time to go through all that stuff as you get more and more familiar with the unit. For now, just plug in, and have fun!