Getting to know the members in your guild is the first step. It's best for leaders to create a group chat outside of the game, as the in-game chat system isn't the best tool available.

For example, leaders can create a discord channel and place the invite link on the Guild Announcement so that members can join the channel. Besides talking about the game in the channel, leaders can also encourage members to chat about their daily lives. It's best if everyone can get along well and become friends.
Next is event reminders. In the group chat, leaders can remind members to join guild events. But be careful not to overdo it or your members may find you annoying. In the [Clash at Hanzhong] event that will be released subsequently, which will match guilds randomly for battles. Leaders can send commands and lead their members in the attack during the event.
When everyone is getting comfortable in the group chat, leaders can begin to set rules for the Auction House. For merchant or auction items with placed bids, some guild members may ignore them and offer a higher bid, or purchase auction items at the buyout price to win the item immediately. This may create a negative experience for other guild members.
Setting Auction House Rules
If your guild is able to get the Jade of Kings in Siege, leaders can set rules that members will bid for the Jade of Kings in the order BR and placing a higher bid is not allowed. When the member with the highest BR has reached 5-star Jade of Kings (more cost-effective), the next member will be allowed to bid for the item.

Besides Jade of Kings, other cost effective items include Tokens (i.e. Titan Edicts) that can be used to upgrade titles and Satin that can be used to redeem hero skin.
For Tokens and Satin, leaders can implement the Fastest Finger First rule and buy the item at the lowest price. Other members are not allowed to place a higher bid but they can buy it with the buyout price (especially for situations where members only need 1 item to upgrade titles). If anyone places a higher bid, the member will face a penalty by buying the item at the selling price.
I have only provided examples for your reference. Leaders can set their own rules based on the situation of the guild. If guild members are close with each other, they should be kind enough not to bid for items that already have a bidder.
Guild Member and Guild Management
Guild leaders can assign up to 3 active members as deputies. A deputy has the authority to upgrade the guild building, approve guild application and kick a member out of the guild.

For leaders, it's best to stay connected with your deputies so that these active members will stay in your guild. If they decide to switch guilds, it will also greatly weaken yours.
For ordinary members who are offline for long periods of time, or have already quit the game, you can kick them out of the guild. In this way, you will free up vacancies for new active members and ensure that your guild remains competitive.
Guild leaders can also connect with each other and form an alliance. Guilds that have formed an alliance can agree not to attack each other in the Dragonboat Race in order to maintain the guild ranking, or team up to attack other guilds. If many guilds form alliances, leaders even can discuss whether to combine into a larger guild and conquer Luoyang City!