Rule No. 1: LIE...........tell them you're horrified at your behaviour, and that even though Jehovah may forgive you, you find it hard to forgive yourself. This will impress the elders as they are looking for weak minded people with low self-esteem that they can control and dominate. And nothing makes an elder feel better than pointing out flaws in others - it makes them feel that all the child molesting they've been doing, isn't really that bad compared to whatever you did..................
Tell them that you miss going out in service (only an elder would actually believe this) and the association of the brotherhood. This will give them the impression that being cut off from your family and friends is a deterent from you ever sinning again and therefore, they won't see you as a threat.
Depending on what type of people these elders are (are they young, new elders, or old fashioned elders?), you might let your eyes well up with tears, but try not to "cry" too much.......just enough to make them think that you're really changed...........if they're older elders with old-fashioned ideas, try to convince them that not only have you changed, you've gone a step further in "pummelling your body". For example, if you got DF'd for committing fornication, you tell them that not only have you stopped fornicating, but you've also trained your mind so that you don't even "look at a woman with passion in your heart".
They'll most likely fall for all this, if you can do it with a straight face. Let us know how it goes.