How do I level up ?
By killing other Ninja. Once you have enough kill points, you'll be levelled up automatically. You can visit the Dojo to get a listing of what will change, and what kills you need.
How do I attack another ninja?
You can attack another ninja by selecting fight from the main page clicking a ninja's name, or viewing the list of ninjas on the "player list", then click their name and attack them from their profile page.
I need turns, where can I get them?
You can use amanita mushrooms once you buy some from the shop with gold, or wait for the half-hour and you will receive a few turns automatically (more if you have the "speed" skill).
I need gold, where can I get it?
You can get a gold from NPCs, killing other ninja for a fraction of their gold, or Working in fields on the Map, which will let you trade your time/turns for gold. Also, the Doshin Office keeps a list of ninjas who sometimes have bounties on their heads. Killing those ninja will get you the bounty as a reward.
How do I attack an NPC?
Choose the Fight link from the main page, then click an NPC's link. Most NPCs only give items and gold, not kill points, with the exception of the Samurai, who is very difficult to kill, easily a match for any ninja.
How do I use items?
There are two ways. Either go to your own Inventory, where you can use stealth scrolls and speed scrolls on you-rself, or go to another ninja's page from the ninja list and then click on the item to use it against your target.
How do I use my skills?
Different Ninjas have different skills based on ninja class. Either click the Skills link from the menu for any skills that you can use on yourself, or find an enemy ninja's profile page and click a skill to use it on them.
How can I talk with other players?
You can message players from their profile, send a message to all your clan members from the Clan link if you are part of a clan, or post public chats to all players on the full chat board. To check for messages sent directly to you, click the Messages link on the main page.
How do I join a clan?
View a clan and make a join request when viewing their clan page. If the leader is active, they'll get a message and respond to let you in or not. If not, you're free to try requesting with any number of clans, or you can make your own once you reach about level 20.
For various other info, see the Wiki