Find ways to involve him in all the things you have to do every day anyway. If you need to make breakfast and then lunch to take to work in the mornings, find a way to sit him at the counter to "help" you (you can give him things to snack on, play with, hold, etc.) or wear him in a wrap and talk about what you're doing. Same with dinner or after work household tasks. If you have big things you need to get done, save them for the weekend when you can trade off with your partner on one-on-one time, or do them in the evening. My daughter is a quite a bit older now, but I work full-time. We make sure both of us are home mornings and evenings, and one of us is always giving her our full attention (while the other does dinner, etc.), she also stands at the counter and helps with meal prep, or goes outside to help one of us in the garden. Basically, one of us is always actively with her. No tv or playing alone. We also as much as possible make weekends family time. We don't go off and do our own things on the weekends. We also rarely schedule playdates. She sees her friends all week at nursery. We make weekends about family. We're all together just as a family because we don't get much extended time together during the week. It means we don't get to pursue our own interests or activities alone or see friends alone very often. Maybe a couple times a year one of us goes off to see friends for the weekend or we do have to travel for work, but we really try to be together as much as possible, including sometimes all going away on work trips together. It means we don't get loads of adult time, but I think it's a worthwhile trade off since they are only little once.
