Many of us suspend our harnesses from the loft or garage to set it up for comfort. This works OK and is a good way to ensure it's not too uncomfortable prior to a test flight. But, invariably, it never feels the same as when we are in the air flying. There are a number of reasons for this, primarily, the risers being vertical rather than at the correct angle – not much you can do about that.
However one thing that can make the ‘flying the landing or garage’ experience more real, is by putting all the stuff we normally carry in the back of our harnesses (rucksack, camelback, cuddly toy, sandwiches, etc) in place, as it can make a major difference to how the harness feels.
Try it, it works for me.
Nasher
Previous post on harnesses here:
http://www.swwsc.co.uk/index.php/topic,673.msg3576.html#msg3576