I run a monthly 8 hour game on a Saturday. Which Saturday changes based on player availability.
I much prefer a longer game. 4 hours is to short. You generally end the session in the middle of a dungeon, etc. So if you have weekly 4-hour games, it seems you frequently have to have someone run another players game. I try to have my session end with a quest complete. If some misses the next game, their character just was not part of that mission.
Frequent, shorter games work best when you are in high-school or college, or have a group of players with no kids and 9-to-5-forget-work-when-you-leave-the-building jobs.
If you have players who are parents and professionals, it gets more difficult to keep up a campaign of frequent, shorter sessions.
To make the infrequent, lengthy sessions work, consider some of these tips:
ONE: Use a scheduling program/service. I use Doodle. Trying to schedule sessions by e-mailing people back and forth sucks the fun out of life.
TWO: Use milestone leveling. Don't bother with XP.
When I started my campaign, I had a complex XP system based on ideas from the DMG. You had normal combat XP, XP for solving different levels of challenges , and XP for reaching certain milestones. What a way to turn my game into an accounting task. Even more problematic, it would take YEARS to level up through all tiers. Now I level up per session. Each month we play a different level. That weay we can experience all levels of the game in 20 month.
THREE: Focus on adventures more than campaigns.
I hate writing this because for about half a year before starting my campaign, a created a detailed world with a number of big story lines. While a map and some details on cultures, groups, and regions are helpful, now I think you just prep for your next game and let the storylines build themselves in reaction to player decisions.
CONSIDER THE SEMI SANDBOX
It is hard to plan for a long session and have the players decide not to take the bait. This is how I handle that. At the end of a session, I role-play and metagames with the players to determine what their next session will be. At this point, there are so many rumors, storylines, loose strings, and my huge world map, that the players can basically decide what they want to do and where they want to go. Then I spend the month preparing the next adventure based on that, for the new level they will be playing at. If, at the next session, they decide, nah, we no longer want to do that, I used to have some drop-in adventures, which worked well at lower levels, but it is getting very difficult to accommodate that at higher levels. If they change their minds between sessions, we are pulling out the board games.
OR, JUST RAILROAD
Monthly, long sessions lend themselves to playing old school. Play a module per session. The Tales From the Yawning Portal is a good book to use for monthly, long sessions. Players don't choose where to go. They start the session at the location. DM just says, you followed a rumor and an old map to the Shrine of Cum'tu`dai, as you search the ruins of the city it was supposed to have been located, you fall into a hole ..."
... and the session starts.
