Help me figure out a routine please!

[OhWhatNoooow]

I desperately need to bring a routine into my household which is 5 DC ages 5 weeks

Is that 5 children at 5 weeks or 5 children one of which is 5 weeks

sorry, pressed send my mistake...

ages 5 weeks, 3, 5, 8, and 10. Until now we have been winging it, not having set times exactly for supper and bed and the kids walking all over me. The middle 3 come home from school at 4:30 and I thought to feed them supper first because otherwise they snack on rubbish if I feed them later. The oldest comes home at 5:30, then he would eat his supper. Then homework and playtime. Then extra snack if anyones hungry and everyone upstairs for showers and pyjamas. The older 2 could come down to do homework afterwards while i put the younger ones to bed. The baby doesnt yet have a set routine although I've been bathing him and feeding at the same time as the younger ones.

The things is, the kids tend not to listen to me when I tell them to come for supper or now its bedtime and there is always something else they want to do or need to have. Should I be strict with the routine and just say no when they try to push the boundaries? How do you stick to your routine so that it works? What do you do if your child refuses to cooperate, like take a shower? Tonight my daughter 7yo refused to take her shower so I just left it and told her she couldnt play on the ipad tomorrow.

Can you come up with a routine that might work for me?