Hi and welcome to the forum Craig
Firstly I will touch on the safety side of things with Mogo and not to scare you but just so you are prepared more so
Some parts of Mogo are full of old deep mine shafts, some are fenced but 99% of them are not, I know it seems like common sense but dont walk backwards in mogo! (any gold field really), a few spots are so overgrown you basically cant see the opening of a shaft till you have stepped into it so please take your time
Plenty of snakes around there so take your first aid kit with snake bite preps with you, if you dont have one let us know when you find a good deal on them when you pick one up before you get there.
Take water cause despite the shade of the lovely state forest and proximity of the coast it gets hot there and it is meant to be fairly hot this weekend as far as I heard, drink plenty rest often
Now the good stuff you want to know, there is plenty of gold in Mogo it just makes you work for it, mostly it is smaller gold but the old nice one comes up now and then, if you go in on runnyford Rd and take the left onto Ross ridge Rd (first major left really) then a few hundred meters on your right you will start to see a few little tracks, most of them will lead you to the old diggings on that side, that is a good place to start, swing low and slow, dig everything and double check your holes (before filling them back over), if you were local to me (Shellharbour) I would of lent you a really good map of Mogo I have
I get down as often as I can so maybe next time we can explore some more and there is a few of us that regularly are out there so you may run into one of us out there on the weekend
Best of luck and happy hunting
Cheers
Jamie