Keep it organized
It sounds pretty obvious, but a tidy bank is a good sign of the guild's organization as a whole. Members plunk items into the guild bank but don't always take care to put it in the right spot. As a result, it gets harder for members to find items they need, and useful resources and upgrades end up collecting dust in the bank.
If possible, try to separate out items based on type, like crafting materials, gear, spells, consumables, or jewelry. But also consider setting aside an area for members to pass items to other characters on their account. Players often get decent items that their alts can use, and the guild bank is an easy way of transferring things. Also, there are times when someone wants to pass an item specifically to someone else who isn't online. Having a section of the bank devoted to this purpose prevents another member from unwittingly scooping up something that was meant for someone else.
Another issue to consider is the level of access for various ranks within the guild. Some MMOs allow leaders to customize access so that some parts of the bank can be used by all, while others are restricted to certain ranks. A few years ago, our guild had experienced a wave of hacked accounts. Almost a dozen members had their accounts compromised, and one of the first things the hackers would do (after stripping the characters) was access the guild bank and steal as much as they could. Luckily, our most valuable items were in a section of the bank that could be accessed only by officers, so the only things stolen were easily replaced and didn't cost much. If you can't customize access levels, it might even be worth it to put valuable items on a mule character of a trusted officer or leader (or ideally, give it to someone in the guild who can use it as an upgrade!).
Some members use the bank as a dumping ground for their junk. They might have good intentions, but each worthless item in the bank is one less spot for a decent upgrade. The bank needs to be a central area for members to transfer useful items to one another, so junk needs to be taken out as soon as possible. A dozen level one crafted potions probably aren't the best items to put into the guild bank, so try to gently remind members not to dump common and low-value items in the bank.
Keep inventory flowing
If an item is sitting in the bank for a long time, it's time to give members a final shot to scoop it up before vendoring it. You don't want the bank to be a museum for your guild's loot; you want it to be a temporary holding area for useful resources and upgrades. Not every member is on at the same time, so the bank enables members to access things no matter what time of the day they're online.
One of the pitfalls of running a guild bank is allowing items to sit in the bank so long that they basically lose their worth by the time they're given away. You don't want to frivolously dole out nice weapons and gear, but at the same time, they'll soon be yesterday's news once the next game update introduces a new tier of loot. Get members into the habit of looking through the bank and contacting the leader or officers if there's something they can use because the better-equipped that player is, the stronger the guild becomes overall. And it's amazing how many members don't pay much attention to what's in the bank. The faster your inventory turnover rate, the better off your guild will be.
Open space is OK
There's a tendency for guildmates to want to fill every spot in the guild bank, but it's ok to have empty space in the bank. It's better to have a partially full bank that contains useful items than one where the good stuff gets lost in the clutter.
If you have a guild bank, it might be time for a little spring cleaning. Too often, guild banks become a graveyard for both great items and junk instead of a central hub to transfer items. It's hard to let go of certain items because someone in the guild might need them later on, but if it's been sitting around for a while, it's time to make a "last call" for members to claim stuff before selling it. That way, members can find the things they really need, without having to wade through dozens of useless items. And while you tidy things up, double check your access levels to make sure things stay secure.
Do you have a guild problem that you just can't seem to resolve? Have a guild issue that you'd like to discuss? Every week, Karen Bryan takes on reader questions about guild management right here in The Guild Counsel column. She'll offer advice, give practical tips, and even provide a shoulder to lean on for those who are taking up the challenging task of running a guild.