1) Why not establish your credibility as the new teacher? Do you remember that you were good at school? In all subjects? You actually enjoyed them all! As the new teacher, your role will be to find the right question. Do not worry if your handle on the actual content is a bit fuzzy. When you 'mark' the work, just listen to your child explaining things. If it makes sense, that's 100%!
2) Structure is good. It means your child can have expectations. It makes them feel safe. If you have the time to give all your time to your child then the Steiner way can work. Do not mix flexible learning with abandoning your child to a vacuous circle of brain numbing play.
3) If you work with the resources the school has given your child, have a look at the work and ask yourself: What is the point? When you get it, discuss the point of the task with your child. At this stage, the conversation focuses on your child understanding the point of this exercise. 'Just do it' does not cut it. If your child perceives the work to be designed to keep him/ her busy, if your child does not get the point of doing the work, you will have to sort out the mess. Remember, they are children, they are not stupid.
4) The key question to success home schooling is therefore: How can I get my child to understand why this task is important?
The key to successful home schooling is engagement. It is also the biggest challenge.