4/4 time means that each measure has 4 beats to it. 6/8 means that each measure gets 6 beats, rather than 4. (it is similar to 3/4 time if you're familiar with that except quicker and less waltzy)
anyways, listen to versions of Sugaree such as the original studio recording and the Dead Set version. they have very pronounced hi-hat hits that essentially count out the time for you. listen and count along with them 123,456 123,456. I don't really know how to explain time signatures over the internet any better than that. Count the quick hi-hat beats 6 at a time to get a feel for the rhythm. And listen to the rhythm guitar for the strum pattern.
SIDE NOTE: this seems to be the easiest way for me to play this song, but if you can't get the hang of 6/8 time and want to try it in 4/4 time it CAN also be done that way. For every two 6/8 measures, you could also count a slower 4/4 measure. In this case the hi-hat beats would be counted as triplets, but i'm afraid this might just confuse you more. anyways, good luck. let me know if any of this helps.
peace.
"we can share the women, we can share the wine"