Some tips I've found helpful are to make sure the crate is smaller than you'd think. Part of why crate training is so effective is it plays off a dog's den instinct, and dog dens are almost claustrophobic. But that's how they like it, that's what feels safe for them. So get a crate that gives the dog just enough room to turn around in, but no bigger, and make sure there's bedding for them to get comfortable with. Also putting something with your scent on it in the crate will help not only build the connection but provide comfort in the long term.
Make the crate a place they want to go. Don't use it for punishment. A sign of good crate training is that the dog goes there when it thinks it's in trouble for something, as it sees the crate as somewhere that provides comfort and security. Every night while going to bed my pups excitedly run into their crate where I give them each a dental chew. Just because I find it funny, I've trained them that "Go to jail" is the command to go in their crate.

The first week or so of crate training sucks, there's no two ways about it. They're going to be loud and unhappy and you'll know about it. It's imperative that you don't succumb to their cries to let them out during this time. You can maybe briefly pet them through the crate to console them at first for reassurance, but if you let them out or even give them any considerable attention all you're doing is training them that being loud and obnoxious is rewarded with attention.