Meal plan, organise quick easy dinners you can grab from the freezer, and breakfast and lunch options that can be put together quickly and easily. Order groceries online if you can, and keep plenty of snacks in the house.
Lower your standards, your house will be more untidy, less stuff will get done, more tv may be watched. Don't sweat the small stuff, just do what you can.
Get the toddler involved if you can. Dd came along when ds was 21 months, before she was born we got him a baby doll, and changed its nappy, fed it a bottle etc. He was keen to help when the real thing arrived, and that attitude has continued, she's 9 months now and he's teaching her to crawl.
Also if your toddler doesn't have a decent sleep routine, get one in place now.
Accept that it will be hard work, but if it feels like its getting too much, remember that this too will pass. Six months or a year from now, they will both be very different kids.