You might want to try this one - it was pretty common:
Imagine you're sitting in front of an open book. One page on the left, one page on the right. Two columns on each page.
On the left page, the writer usually noted the baptisms. The names of the children and their parents and the date of the baptism (not always also the date of birth) are written in the first column. Another important part of the baptism entries were the godfathers and godmothers. You find them in the second column.
The right hand page is a bit different. You find two types of entries here.
Usually, the left column tells you who got married. The right column deals with the burials.
You can imagine that in most years, the number of people getting married was way smaller than the number of people who were born or died. This fact gave the writer opportunity to jot down other things as well. So it's worthwhile to check the otherwise "empty" spaces as well...