Hi Kel,
Iggy is quite a good sleeper and we do the following things:
1. Firstly when he is awake we make sure he has some interesting activities to do. If he is absorbed when he is awake he tends to sleep a whole lot better.
2. I listen particularly for his tired cry and his stare eyes and know he is getting to that point.
3. I put him in his day sleep area - this is propped in a v shaped pillow on the couch next to where I work on the computer. I then pop in his favourite dummy which he is allowed during the day but not at night. NB I put him on the pillow even if he is grumbling (but not really crying - more the whingy type grumble) because the more I hold him the more stimulated he seems to get.
4. He doesnt like quiet while he sleeps because I think he feels alone then so I put on the tv or some music and make sure I am not very quiet. Sometimes I make little grumble noises or I move around the room so he know I am there.
5. I sit next to him while he settles himself although I don't look at him cos it seems to keep him awake. If he actually gets properly upset eg cries then I pick him up because he usually needs a nappy change or something instead. If he is just a bit grizzly (sometimes he grizzles while he is sucking - so cute!) then I just stay with him but not fuss over him.

HTH. Its hard that every little bub is so different. I also like the teddy bear idea that someone else brought up.

ps. If you dont like them to have a dummy you can try what I do at night. Occasionally he needs a dummy to calm at night but I dont like him to have one overnight. Once he is settled (and in a period where he is not sucking) I can usually pop it out and he will still go to sleep without fussing.