Just that really as I don't really know what approach to take. DS is 5 and generally lovely but can be very dictatorial - I.e saying things like "we have to do what I want to do" and demanding DH and I don't talk to one another. He is mainly like this at the weekends when the three of us are together most of the day - during the week when it is mostly just me with him or occasionally just DS with him he is a lot less bossy and a lot more reasonable. It's funny because to other children he wouldn't say boo to a goose - he's like this with adults only (he can be like it with his grandparents and aunties and uncles too, bossing them about and demanding they do x,y,z).
How do you deal with that sort of thing in a way that actually works?