Oskar was around 6 months or a bit more before he really slept in his cot during the day. Now he's great with it. I can even put him in awake sometimes and he'll chat away then go to sleep.

He went through the stages of - only sleeping if I held him - up to around 2ish months old.
Then it was only on his belly up till around 4ish months old.
Then we were ok to sleep on mum and dad's bed until around the 6 months where he was happy to go to his cot.
Funnily enough he slept in a hammock at night ... EVERY night until 6 months but didn't like it during the day. At first with the cot he had to be asleep when I put him down, but now he can go either way but depends on if he THINKS he's tired or not...lol. He's 11 months now.