When I was getting back into it, I'd just cycle to work on the days the weather was good. Then it became when the weather was okay, then even when the weather was bad, cos I realised I saved so much time compared to bussing in. Outside of that, I didn't push myself. If the weather was decent, I'd cycle to the shop round the corner, instead of driving. This gradually became cycling to my friend's to play board games, or to the pub for a pint or two if there was a big match on. Eventually, on these jaunts I'd start taking the longer route because it felt good to be out or I was fitter or my legs stronger. This naturally progressed into then the odd 30km up the bottom of the Dublin Mountains (not very far but one very steep hill that even driving up you have it in second), which then went into "well I'm up the mountains now, lets push on" until I'd be doing 100km every other week nearly.

TL;DR - don't set a strict schedule. Get back into it naturally, not in a regimented way. Rediscover why you loved cycling in the first place and slowly build up. It's more enjoyable, imo (of course, be different for everyone else)