I would suggest you start off with a regular double stroke pattern and not worry about the 5-stroke pattern just yet on this excercise. Playing this excercise with a regular double stroke pattern makes it extremely easy to play. But, you do this to get used to the feel of the pulse of the bass after every 4 16th notes on the snare. Play it slow and perfect it. Once this is done, without stopping, begin playing the 5-stroke pattern without changing the tempo of the bass or the snare.

Alternate using the sticking pattern I have written above and below the staff for the snare each time you loop through it. In other words if you start the excercise using the sticking pattern I have written below the staff, then next time around you must use the sticking pattern I have written above the staff. Play the sticking pattern without accents at first. Perfect it this way first. Once your able to continuously loop the pattern over and over without mistakes, begin adding the accents. The last step is to begin ghosting all the notes in the 5-stroke pattern except the accented notes. With a little practice you can begin playing the ghost notes without touching the snare (air-drumming). The idea is to play the accented notes on the snare loudly so that they are dominantly heard along with the bass drum notes. Technically, its not a true polyrhythm if you leave all those extra ghost notes in there. But, even if you leave them in there, you will still be training yourself how the 4 over 5 should sound and feel. I think it sounds good either way.