A general rule of thumb I keep is to have a common time that is good for most since we all live in different timezones (evenings work best). Friends like to play with friends, so if you design a private group around a group of friends, it's relatively easy for people to get along with each other. I usually have the date agreed and posted on a week before it happens and have a "sign up" thread. From there, people can either sign up as "Yes, I know I can be there" or "I'm not so sure". For the people who can make it, I send them a few reminder PM's throughout the week. I expect things to change at last minute, it always happens. Although a tip I gathered from DeeJ is that always start on time. You don't know what the schedule of other people is actually like. If you have a set time for an event make sure it's that time. People have jobs, kids, life, homework and jobs. So if people don't show up, start sending out invites to your alternate list/subs. My last tip is keep them as an informal social event. Make sure the guys that actually signed up for the event actually get into the lobby to play, otherwise you have guys that won't show up for the next one. I usually don't keep mine going for more than an hour, that tends to get too long. However if people want to stay and play more afterwords they can. The more you host, the easier it will get.