Vinny

There are essentially three ways you can hookup for Effects Only ...

Front of Amp

     Guitar ==> HD Input

     HD 1/4" Output ==> Amp Input

This is the simplest way and works well for many people.  It works well if you are mainly using the clean channel on your amp or you are only using effects that normally sit in front of the amp(e.g. compression, wah, distortions, some modulations).  It is also OK for amp modelling if setup correctly.  Not always so great for reverbs and delays etc, particularly where higher gain tones are used.

In the Loop

     Guitar ==> Amp Input

     Amp FX Loop Send ==>  HD Input

     HD 1/4" Output Left ==> Amp FX Return

This way works very well for effects like echoes and delays, reverbs and some modulations.  Not so well for distortions and wah.  Amp Modelling will almost certainly sound weird.

Four Cable Method (well actually more cause of the stereo)

     Guitar ==> HD Input

     HD FX Send ==> Amp Input

     Amp FX Send  ==> HD FX Return Left

     HD 1/4" Output Left ==> Amp FX Return

This is the all singing, all dancing method for hookup.  It allows you to put all effects where you want them, to use your pre-amp channels correctly and allows for amp modelling too.  It is a pain to intially get your head around and setup but the results can be excellent.  For more details on 4CM and what it does check the link here.  http://line6.com/support/docs/DOC-2523

Hold down the View button until the display shows a new page. In the top left corner you will see "<1/10>". Hit the right nav key until you get to page 4 - "<4/10>". This is the Outputs setup page. Rotate knob #1 to slect one of the output modes designed to connect to an amp (NOT Studio mode). Select the mode (e.g. front combo) that most closely resembles the way you are connecting to your amp.

For details, see the HD500 Advanced Guide page 2.9

Well I started my patches based on a few models.  I use, I think, the Hiwatt model with a Celestion cab for all of my clean tones, and another model which I can't remember at the moment for all my dirty tones.  I then built every other patch off of one of those base tones, with the footswitches set for the same model/effect on every patch, so that the controls would stay the same across the board.  It usually isn't a problem when I switch off the amp model, since I only use one standard combo amp for practice.  So far as I can tell, it's close enough for me to work with.  The other benefit to this is that I have LED confirmation on whether the amp model is on or off when I switch on a patch.