Go over household duties and divvy it up in a way where everyone knows what is expected of them and so one doesn’t do more than the other. This avoids resentment in the long run. And lower your expectations when DH does it. Lol. Then when the kids are older you can offload them as chores.
Same with looking after DC. School runs, getting ready in the morning, bath time, bedtime, GP appointments, school shopping, etc. you should have a discussion on who can manage to do what so it’s fair.
Finances: Have separate bank accounts and one for joint expenses. Get a spreadsheet going and talk about your finances. Go over expenses, savings and financial goals. It’s best to be on the same page on this so you don’t fight about money.
If you can afford to outsource things so it makes life easier then do it: cleaner, takeaway every now and then, etc..
Make sure you have time for yourself and your DP as well.
Make time for date night. even if it’s after the DC go to bed and you are watching a movie on TV.
Make a pact to try and be forgiving towards one another when you are both lacking sleep and are irritable.
Work to make sure the communication is strong in your relationship. If issues arise, don't guess and don't assume. Just talk it out.
DH and i have been married 6 years and together for 8. We have 2 DC (4 and 1) and as much as we love them they do wear us out. Juggling marriage, careers, kids and personal goals is hard but it's worth it.