I like watching it when we've got rid of (most of) the duds & the show is not so goddamn long.
So I wait until at least four have been eliminated (may wait for 6 this year tbh) & then Sky+ it & fast forward Shouty-McShouty, Titilation (although this year it's Rabbit-in-the-headlights) & any judge that waffles on too much - plus of course the ads, the boring VT's & the intro. I get it down to barely an hour .