One tip I found really helpful with my little one was to create a visual schedule for the day, especially if they're having a hard time communicating their needs. Drawing pictures of the activities and sticking them up in order gave some much-needed visual clues about what's coming next - it helped soothe temper tantrums because she could see what was happening next and also taught her to identify and manage her feelings a bit better.
Also, keeping a consistent bedtime routine with very little stimulation (dim lights, quiet voices, no screens) seems to help with sleep. But I think the most helpful thing for us was setting very clear expectations and following through - it's amazing how quickly toddlers pick up on what's acceptable behaviour and what's not if you're consistent!
Would love to hear other people's tips on managing the daily challenges - especially any tricks to get kids to eat veggies!