...
The basic idea is that babies need to learn to fall asleep without "crutches," like nursing, getting rocked to sleep, or sucking a pacifier that parents have to plug back in throughout the night. Apparently everyone wakes up several times a night, but they fall back to sleep so quickly that they don't notice. Babies who haven't learned this skill rely on their crutch to get back to sleep. So you teach them to use techniques like thumb-sucking, snuggling a stuffed animal, or hugging a blanket to fall asleep. Then they won't need anyone to help them fall back to sleep throughout the night.
You put your baby to bed "drowsy but awake." He should be tired, but not already sleeping or on the verge of sleeping. You want to make sure he gets to that point by himself, not by getting nursed or rocked. You sit next to him to provide reassurance while he falls asleep, before it escalates into a full-blown cry or tantrum. You can touch him for comfort, but don't pick him up or play. Make sure it's dark, quiet and boring in there (no mobiles or toys) to encourage sleep. As he gets used to it, try to comfort him with only your voice. When he's ready, move the chair a little farther away each night, until it's just outside his door where he can't see you. Continue comforting him with your voice, so he knows you're there. Eventually you won't need to wait around any more.
......
I am personally against the crying-it-out method. I don't think it's abuse, but I do think it's a poor choice. (Like teaching a child to swim by throwing him in a lake... yeah, it'll work, but it's worth the extra effort to develop their confidence and teach each component in stride.) Being there to comfort your child, while being firm that he needs to sleep, helps him to be receptive to the idea. How you teach and discipline your child now sets the stage for how you interact with him as he gets older. If you are patient and receptive to his needs - without giving into his demands - you can develop a nurturing and trusting relationship. If you set a precedent of hurting him to correct behaviors, or ignoring him when he expresses his needs, he will avoid your parenting as much as independence allows. (Hurting and ignoring are essentially what spanking and crying-it-out are.) Spanking is neither age-appropriate for an 11-month-old, nor effective for sleep-training. It's an act of exasperation. Think about the long-term parent/child relationship and how your approach affects that, not just how it achieves each goal along the way.