First of all, if you can, I suggest you never go down this route, and you have one home where DC are based the majority of the time, and weekend visits/holidays etc at the other home.
I have DC 50/50 arranged between ex H and I when DC was around 2, DC is now 6 and I loathe it.
Its not good for his mental health either, switching households half the time, and his father situation and mine are worlds apart now. So he switches from one extreme to another.
If I could have foreseen this, no way would I have gone down this route.
DC Is 50/50, one week on, one week off.
Switch day is Monday after school, or 12pm holidays.
I guess its the best out of a bad bunch so to say, he doesnt get moved around constantly, holidays and trips away can still be arranged, on the week I dont have DC I do adult things and have the freedom to do so, he knows what to expect everytime.... no trying to explain to him that Wednesday is daddy's day, Friday mummy's day, this weekend mummy has you, but next weekend daddy has you etc etc.
Its all just after school Monday mummy will pick you up... mummys week/daddy's week.
Its hard to say what effect 50/50 is having on him, I guess I'll only know when hes an adult.
Ive also had to recently go for a hard 50/50 split, as I kept bending over backwards when my ex requested to have my son for longer (family events etc) but when I asked he wouldn't oblige. So now its a hard 50/50, meaning that I shall miss out on half terms (like this week) and Christmas etc.
I get around this by doing things earlier ie. We had our Halloween last week. Xmas will be done after the 'real' day....
Good luck op, I hate 50/50.