You must have somewhere to do it. I've just moved into a place without a garden/yard of any sort, so I'm having to make do. Just take a bucket of soapy water out onto the pavement, with a cheap plastic washing up brush, scrub the hell out of everything, including the chain, lock the bike up, go back to flat for clean water, rinse, go indoors for a cuppa, come out when it's dry, lube the thing up, wipe down with a rag, bring back indoors. Done.
You must have somewhere to do it. I've just moved into a place without a garden/yard of any sort, so I'm having to make do. Just take a bucket of soapy water out onto the pavement, with a cheap plastic washing up brush, scrub the hell out of everything, including the chain, lock the bike up, go back to flat for clean water, rinse, go indoors for a cuppa, come out when it's dry, lube the thing up, wipe down with a rag, bring back indoors. Done.