To enter your daily data, click on the + in the upper right corner, or the date in the 'Calendar' or 'History' view. Enter your temperature and choose whether it's a 'Normal temp.' or a 'Deviating temp.' and any additional data, such as menstruation, sex, LH test result, or a note. Click save and you’re all set! In this view, you can also swipe to the left to go back in time to see your previously entered data. If you have entered any data and swipe back, your data will be saved automatically!
As a new user, you may want to add your previous cycle data. This is very good as Natural Cycles wants to get as much information about you as it can in order to get to know you and your cycle as soon as possible.