How to manage 8 sim household?

Alway have food on the table and make sure you have more than one bathroom!

-I recommend making one a "chef" (not career wise) so they can serve a meal and everyone can grab a plate (just remember to put the leftovers in the fridge! I forget often).

-If you don't want to spend money on repairs, I'd also have a mechanic that's dedicated to handiness and fixing things.

-Definitely take advantage of the "lock door" feature, with that many Sims there's bound to be a ton of embarrassment, so lock the door behind your sim for only him/her and then unlock it once they're finished.

-Make a sim be the "maid" and clean up the house, because with 8 people I'm just going to assume that keeping up with all of the plates, dirty bathrooms, and counters might be a bit tricky, so having a sim be there to clean everything is helpful for no one to get the uncomfortable trait.

-I'm not sure how important the career task/homework is to you, but when a Sim is doing either of those things, or a task in general where they need to be focused, lock them in, that way another sim won't come in and try to talk to them and end up distracting them.

-As stated above, claiming beds is very important, and the more bathrooms the merrier.

That's all I have for you, but hopefully some of these things make it easier.

I had a household of 8, my strategy to keep them happy is to constantly use the "pause" button to make sure all of them are doing the right thing, and I do mean constantly!

Keep a schedule even if it's just with your child Sims, so have them do their homework as soon as they come home from school, have them eat dinner at the same time, around the same time each day (always keep your fridge stocked up with food!), and also keep a bedtime schedule, and have them use the loo before sending them to bed as this will stop them waking up during the night. I also wouldn't bother with child skills, as I find keeping their grades up is more important as it dictates what level your Sim will start out at when they get a career. C grade will start your Sim out at level 1, B grade starts at level 2 and A grade starts at level 3.

Sending your Sims to a community lot or elsewhere can also be a big help, or if you send your other Sims to a community lot and are controlling a Sim at their home lot instead, as the absent Sims will take care of their own needs if you have 'care for self' selected. Have free will on, as I find my Sims are actually very good at caring for themselves, but check on their needs quite often and as kingkong said, have more than one bathroom. I also find the 'auto-solve' button that you find beside each need bar is good to use too. :)

i cant never manage more than 4 sims.. seriously everything turns to hell XD

I'm a large Sim household player from way back. I jumped right in and played the Pleasants ( a family of four ) when the Sims first came out. These are very good tips that have been given. In a family of eight I try to have two or three of them that can cook , two or three that can fix things , everyone gets there own bed , I don't care about the grades when they are teens so I have them work on skills and meeting others OUTSIDE the family , as soon as they are young adults they get jobs and we go fromthere.
Large fams , wild ride that I recommend - have a good time.

Thanks guys for the tipps

USE the pause button, it is your FRIEND. I love large households, but I find it's easier to manage if I employ the pause button, set up the queues for certain Sims and then un-pause the game. Works like a charm.

I don't think that I could do that. My sims only have one child and no one moves out, so by the time the child marries the most is 6 but only for a short time because the grandparents pass away soon after or before

*rolls up sleeves, hitches up pants, sniffs arrogantly like Ralph Furley*

Not to toot my own horn, but years ago when TS1 came out, I put out a story album called "The 8 Sim Challenge." Even though TS4 is different from TS1 in many ways, some of the tips still apply when trying to manage an 8-sim household:

1. Make it so that parts of the household are going to work at different shifts. So, say, have four sims work in the morning and the other four sims work in the afternoon. That way, there's never more than four sims in the house for more than an hour two fighting over the bathroom or making a beeline for the refrigerator.
2. Always designate a sim as the Resident Chef or Repairman by giving him or her high cooking and repair skills.
3. Have a couple of sims be neat freaks
4. When sims are off for the day, have them play housekeeper and master chef. Make them clean the house and cook up a storm.
5. Just buy books for skill building instead of shuffling sims back and forth to venues or having them fight over objects
6. Remember, you can boost their fun and social while they're at work so that by the time they get home, you have two less needs to worry about.
7. But a porta potty if there's one bathroom. They're much cheaper and...Oh, wait, never mind...*paging devs with an object request* :*