1. Click on Settings

office365-iphone6-1

2. Click on Mail, Contacts, Calendars

office365-iphone6-2    

3. Click on Add Account

office365-iphone6-3

4. Click on Exchange

office365-iphone6-4

5. Enter your email address and password then click on next

office365-iphone6-5  

6. (Optional) – If this screens pops up enter outlook.office365.com in the server field

office365-iphone6-6  

7. Choose what you would like synced with Office 365 and your iPhone and then click on save

office365-iphone6-7