Thanks to a few more months of experience, here's an update of my previous hosting tips.

Ratios
For Werewolves of Miller's Hollow you need about 3 villagers for every Werewolf. The Seer is generally recommended as well, and that's probably complicated enough to get started. Have more roles rehearsed and ready, though, because most people hate being stuck as a simple villager.

Jumping right in
I teach non-gamers who are generally restless, so I explain the general cycle of "sleep-bite-wake-lynch" then jump right in. You can explain individual roles as you call up these people to do their tasks. This quick start approach can help with unruly crowds of folks who want to talk about everything but the game. All that really matters is that players can identify what their roles are before the game starts - I provide a playing aid of some sort so people don't have to reveal that they have a weird role just to get you to identify it.


Frequent breaks
The critical thing to remember is that it is positively painful for players to keep eyes closed for prolonged periods of time. You really can't appreciate this until you've played - within minutes, your entire group can end up with a bleary eyed headache. Explain what you're going to do with eyes open, close eyes, do it quickly, then let eyes open up again while you fumble around or explain what's going to happen next.

Secrecy
All the things you have to do sound easy until you realize that it all has to be done with attentive ears listening for everything! Before starting the first night, remember to warn people (especially the chatty ones) that players are listening for movements, sounds or changes in speech that might give something away. Here's some classic examples:

1. You: "Werewolf, choose a victim" - Werewolf: "Ummmm..." - Villagers: all turn in surprise, then bust out laughing
2. Werewolves: goofing and fidgeting - You: "Werewolves, open your eyes" - Werewolves: abruptly quiet

As a moderator, you have to be even more careful and even deceptive. Direct your voice the wrong way when talking to someone. Get used to using formal titles ("The Lovers will now... The Witch will now...") NEVER use the words like "him" or "her"!

Communicating Selected Roles
There are times when people have to choose roles (Bodyguard: "I choose to protect the Witch"). Have a numbered board ready so these selections can be made secretly with one hand (so the player can use their other hand to make it sound like they're not paying attention): You: "Which of these 4 groups is that role in? OK, is it the first, second or third role there?"

Communicating Selected People
For roles like The Lovers, people have to know they were chosen. However, in big tables and crammed rooms, it can be awkward and time consuming for you to tour the room tapping people on the shoulder.

To reduce movement, have everyone hold out their hands to you (eyes closed). Make sure you pretend to reach and touch everyone, but just grasp the hands of those chosen.

Verifying Identities
After Werewolf kills and Seer choices, you have to make sure that no one special was picked. I suggest having people hold their cards up with eyes closed.


Voting
To reduce pointless arguing, you can just have those who are undecided raise their hands and ask questions. When everyone's mind is made up, have everyone point, figure out who the top vote getters are, then get a count.


I wish you best of luck, and I hope you have as much fun watching werewolves gobble up villagers as we do!