There is a tutorial in fieldtrip website but for minimum norm estimation: Source reconstruction of event-related fields using minimum-norm estimation - FieldTrip toolbox.

The approach is pretty similar for sLoreta. You only have to adapt the ft_sourceanalysis function to include the corresponding parameters.

There are also more tutorials in the workshops page of fieldtrip.

FieldTrip courses and workshops - FieldTrip toolbox

Thanks @Vasilis. But most tutorials are PPT slide based and not hands on. Difficult to imagine the code structure and how to put the structure for initial Syntex is what I'm looking for.