DS started sleeping through shortly before his birthday. He still sometimes wakes up once but settles quite quickly.
No magic formula I'm afraid but here's what I did in case it helps...
1. I hate the idea of leaving baby to cry so never did.
2. We started having a bath, story & milk, & into cot still awake every night from about 8/9 months. We usually start the routine about 8 so that he's tired but sleeps to a reasonable time in the morning.
3. I stopped feeding him when he woke in the night at about 9 months. I started offering water instead. We had a couple of horrible nights where he screamed for up to an hour at the time (while being cuddled by Daddy so he didn't smell of milk) but he got used to it surprisingly quickly.
4. I think the big thing was getting him to fall asleep on his own at the beginning of the night, so that when he woke up in the night he could settle himself again. It was hard work but we don't cuddle him to sleep at all now (I miss it sometimes but it's worth it). Even now he will not settle immediately 1 night in 4 and we'll have to go in and out of his room up to 25 times before he drops off
. Because I don't like CC or CIO, I go in as soon as he cries, lie him down again (don't speak to him or cuddle him) and go out again. If he starts crying straight away I repeat to infinity. That's the theory anyway but I often cave in and sit with my hand through the cot bars stroking his face til he falls asleep!
My next worry is him moving into a bed in September, but we'll cross that bridge when we come to it...
The other thing is if there is anyone (Grandparents?) who can have baby for just one night to give you a little break then one uninterrupted night's sleep can give you such a boost that it will see you through to at least the second birthday
As an ex-no-sleep-club member I really really can sympathise but it will get better without you realising (I didn't post about DS starting sleeping because I didn't want to jinx it!).