When they're tiny, I tend to use a side car and keep them wrapped, so just feed and push back to their own space. Once they start wanting to sleep right next to me (ie wake when moved, the magical 4 month sleep regression) I stop swaddling and start using a sleeping bag. Then I feed and wriggle down the bed. I turn the pillow so there is nothing near baby (so I sleep on the edge of the pillow) and pull covers up to my ears while only going over bub's legs.

Then as they get bigger again and want boob all night (more like 8 months for mine) I lie on one side with my arm out and knees up and bub lies in line with boob and under the covers.

Once they're crawling I start rolling away from them at night because they can wake you and get in and out of covers etc.