It can seem daunting at first, but if you’re having trouble keeping your space nice, one of the best motivators is to either hire a housecleaner or have house-guests once a month.
It’s not because either of them will tidy your house, but because you will tidy your house knowing that they're coming.
(Most cleaners will reliably clean all surfaces that don't have objects strewn across them, so you’ll tidy both to avoid their judgement and to get more bang for your buck.)
See also: KonMari