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When your account is activated, you can login on the page https://login.xero.com/.
If you log in the account for the first time, Xero will ask you to create an organization. Enter the name of your organization and choose other information. Press on Start Trial, or Buy Now to continue.
Now you can create a new consumer key after login your Xero account.
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How to create a new public key
Go to http://developer.xero.com/ > Docs > Advanced Docs > Public/private key pair > Using OpenSSL and run 3 commands to create 2 files: public key.cer and private key.pem
+ Copy and paste content file .cer into magenest/xero/etc/certs/magenest.cer
+ Copy and paste content file .pem into magenest/xero/etc/certs/magenest.pem
When you have file Xero/etc/certs/magenest.cer, copy and paste them into X509.
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Check the information again then choose "I have read and agree to the Xero Developer Platform". After that click Save button.
If everything goes right, you will see the following content. By now we have done everything on the Xero site, now move to your magento 2 backend but don't close this site.
Click on "Show" button to get the Consumer Key.
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At My Applications tab
Taking Consumer Key that you have just created and paste into Magento 2 backend configuration. Press Save Config after you've done (refresh the cache if needed). Then, click on Connect Now button.
Note that you need to save config before connecting, this will help you avoid making the consumer key error.
Connection Status will be transferred from not connected to connected with all the information like the picture below.
At Configure the Accounts Types in Xero tab
Admins are able to synchronize four account types: Bank account, Sale account, Inventory account, Cost and Good Sold account from Magento 2 to Xero. Enter name for each account then click on Sync All Accounts Now button. The default Xero account value will be used if you do not change it. If there is no account on Xero site, the extension will automatically create a new one. 
Admins can check accounts on Xero web.
Set up Synchronization
Admins are able to decide whether to synchronize data in Synchronization Settings tab: Customers, Products(Items in Xero), Orders, Invoices, Credit Memos. In addition, admins can choose the way to synchronize data between Immediately mode and Cron Job mode. Admins can click on Add All Customers To Queue button to add all existed customer data to queue. It is the same with Products(Item in Xero), Orders, Invoices, Credit Memos tab.
How to distinguish between Immediately mode and Cron Job mode.
- Immediately mode: the data will be synced as soon as they're created or updated.
- Cron Job: the data will be queued and will be synced together in some minutes.
Some application mode like private mode only allows 1000 requests a day. Choosing Cron Job will guarantee all data will be synced. We recommend you should use Cron Job mode to make sure that you don't run out of request per day.
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At the end of Configuration, admins can use "Add All Data To Queue" button to add all existed data to Queue, including Customers, Products, Orders, Invoices, Credit Memos.
Process Synchronization
If the App mode is Cron Job, Queue page is the place which the created, updated data is stored in and are waiting to be synced. If you wish to sync data right away, you can press Sync Now button.
Note that synchronizing will take some time, the length of time depends on the size of database. 
When the process is done, go to Xero Integration > View Log check what is synced in the grid.
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Moreover, admin can easily check the synchronization with View Request Daily button and View On Xero button.
Navigate to Xero Integration > Request Daily Report, admins can easily follow their sychronization status.
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Main Functions
- When a new account is registered in frontend of Magento 2, Xero Integration extension will automatically add a new record on Xero site.
Or you can click on Sync Now button of each customer to synchronize a specific customer data manually.
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- Whenever admin creat a new order, invoice, and product or edit them on Magento 2 store successfully. The data will be synced to Xero automatically.
- Orders
Admins can synchronize a specific order by manually, click on Sync Now button on each order.
- Products
For each product, this extension created Xero Integration tab that allows admins to synchronize a specific product to Xero.
- Invoices + Credit Memos:
Synchronizing a specific data is the same with Invoice.
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Update
- When a new update is available, we will provide you with a new package containing our updated extension.
- You will have to delete the module directory and repeat the installing steps above.
- Flush the config cache. Your store and newly installed module should be working as expected.
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