The rhythm I use for the accompaniment here fits in with the first two bars of the melody of Eddie Kelly's jig, in a pattern like that shown below.

Before long, the space in the second beat is filled with an up-stroke and the rhythm thereafter is a regular down-up-down stroke pattern.  Chord changes are emphasised with a slightly heavier down-stroke and I shift the rhythmic emphasis in the highlighted bars in B3 to add dynamic variation.  

The chords are played on the sixth (last beat) before the bar where the fit and then continued through the bar where they belong.  Moving the beat across the bar like this is called syncopation.

In Jerry's beaver hat, the rhythm continues in the same style.  As I strum, the strings are damped, with the heel of the right hand,  You may find it easier to try this style with a soft plectrum at first, until you get used to the feel of it.