I have a great boss, we both get on VERY well! thought id make that clear 1st, and ive been there 6 months
At first my boss would arrange the odd afternoon where a freind (and their mum) would come around (my charges are 2 and 4 so mums normally come too). She may say "shall i arange someone for wednesday... i would say fine!"
Now I have been their longer i often arrange these things myself.... meeting mums in the playground etc! i Always tell my boss whats happening!
We have a diary and its sort of a whoever gets something in there 1st gets priority sort of thing!
As for nanny friends, my boss is absolutly fine that they come around with their charges (as long as the children like each other!) well luckily all my (2) nanny freinds have charges of similar ages to mine and who get on VERY well
If for example i have a friend around, and a mum calls to see if there freind can come around ASWELL (ie i have 4 children) then my boss will always phone me 1st... (genearlly i always say yes, except once... the family are having building work and we go 5 mins up the road to a little flat, and the thought of having 4 children squashed in there (if it were to rain) really did not appeal so then i said "no" and that was fine!)
As for afternoon activites... i have 'found' a few to go to, but mum found a swimming class / ballet class that she wants them to go to, so thats fine i take them!
I always take them to adventure playtime at the local leisure centre, and used to go to tumbletots a bit further away on a friday... anyway mum found an arty craft class for 2+ yearolds on a friday only (much closer to home) and she REALLY wanted them to try it.... we did, they LOVE it so now we do the arty crafty class instead!
I think the key is to have an open realtionship with each other and both be happy to answer honestly... i felt i COULD say no when asked to have the 4th child (when alls quiet in their hosue i dont mind at all!)
The diary works well too!
As ive been their longer and got to know the 'school mums' more i arrange more with them and just tell my boss, but there are a few friends NOT at school with my charges and genarally my boss organises them!
Im very easy going and happy to go along with what my boss requests, and at the same time as long as the children are happy she doesnt really mind what we do or who we do it with!
Hope that helps!