The fuel management is fairly critical, but if you forget it won't kill you. For the 190A5 and D9, burn off 75% of the AFT tank, then switch to forward. Once you get down to 25% in the forward tank, it is time to go home. 25% of either tank will get you about a half-sector if you are flying at sea-level.
In the 190A8, burn off the entire AUX tank, then 75% of the AFT tank, then the FWD tank.
That is how I do it anyway, and I gather that is the 'standard' way to burn off the fuel.