We are very boring and often do stay at home all day. DS2 is 13mo. (DS1 11).
Definitely don't try to entertain the toddler constantly - how will they learn to entertain themselves? Admittedly, DS2 has always been extremely self sufficient, but for example today:
I got up with him around 8am. DH had a lie in.
DS2 emptied all books from book shelf, pottered, climbed on sofa, took all his clothing out of the boxes it's stored in, looked out of window etc. DS1 got up and played with him for a bit but he would have been equally happy (probably happier) alone.
Probably about 9.30 I got around to changing his nappy, getting him dressed, making coffee and breakfast. This probably took about 40-60 minutes as we were not rushing.
DH got up at 10.30, chatted/played with DS2 for a while and did some cleaning up. DS2 went onto balcony to look outside for a bit. Came back in and was tired so put him down for nap (11ish)
I went for a nap at about 12. DS2 immediately woke up so put him into bed with me and we both slept until about 1.30.
DH spent about an hour cleaning kitchen and slowly making lunch. I tidied the messed up clothes and put some washing away. DS2 pottering in kitchen being fed slices of apple/"helping" with dishwasher (I took him out, and we closed the kitchen gate, so he then played next to the gate while eating slices of apple)
Changed nappy, ate lunch (very late unfortunately) it's now 4.45, and DS has been pushing his wooden truck around the house and commentating on things for the last 40 minutes or so. I've put more washing away and gave him the odd socks to play with, which he has enjoyed putting them into his truck and taking them out again. DS1 has been cajoled into doing his homework. Robot hoover started beeping so DS2 went to investigate that and try to bring it back.
DS2 got a bit bored/tired about 10 minutes ago and wanted some milk, but has now gone off to play again. I can hear him putting things in and out of his truck still but not entirely sure what he is doing. I will check in a minute. :)
It's almost dinnertime, which will probably be a light snack since we ate lunch so late. Then he will have a bath and get ready for bed at 6. Some days we let him watch a bit of TV (he likes music/nursery rhymes on youtube) if he gets tired and grumpy for example in the afternoon but I don't think he'll need that today.
We did go out for the whole day yesterday, though. So it is probably an unusually slow day for us here but we do quite often spend our Sundays like this.