At that point we were still in chaos! So good on you for starting to think about this. We managed to implement a sort of routine at about 7 weeks adjusted, basically bath, book, milk, bed with a dark room and white noise machine at about 7pm, dream feed (which we did start waking them for) at 1030, then normally a feed around 3-4am which we started trying to push out as long as possible with resettling and shhhh, then 7am, 1030am, 1pm, 430pm feeds roughly.
We also (like PP) tried to avoid picking the boys up as much as possible to avoid them getting used to it, and also because I physically couldn't get two up and rock them, so we did a lot of bum patting, gentle forehead stroking etc. They seem to be able to settle themselves much more easily at a younger age.
The other difference we found with them sleeping was moving them into their own rooms which we did at 4 months. Obviously that is not official safe sleep advice and I did my own research before doing that but we were all waking each other up all night and I was so sleep deprived that the alternative was me having a breakdown or accidentally crashing the car / walking out under a bus.
The boys are really good sleepers for the most part now although the full nights sleep for us didn't really happen until they were eating a decent amount of food during the day. I do think having a bed time routine from really early has helped with them being comfortable going to sleep independently.