Tutorial for source localization of resting EEG?

Dear MNE experts,

I am wondering if we have any tutorial for source localization of resting EEG with MNE? I have 64-channel resting EEG data of 5 min and want to do some theta-gamma coupling analysis after source localization (so I need signal within 1-100 Hz range). I guess I have to split the 5 min into epochs since it is too large to invert. Do we have any recommendations on splitting resting EEG data? What could be an ideal length for each epoch?

Thank you!