Sleep help!

[Myleo]

Baby is currently almost 4 months. Sleeps pretty well throughout the night waking for 1 sometimes 2 feeds still but always goes straight back off after. The problem is initially getting her to sleep at bedtime. She wakes up crying after around 30 minutes of being down and then can take 2 hours to get back to sleep. Any ideas or advice?

I know this question is the bane of every sleep troubled parents life - but when you initially put her down, do you put her down awake?

My son is 3 months and when I put him down awake he does a lot of fussing (we call it "cat in heat" noises), we leave him to it and only go and get him if he cries. Sometimes the more we try and intervene the harder it is to get him to sleep - however I totally appreciate every baby is different.