verfassen

fassen means something like to grab. The change-ver shifted that toward a more long lasting grabbing. A bit like to frame. The use is pretty specific  though because verfassen only works for capturing thoughts essentially making it a fancy or formal or pompous alternative for to write. You can verfassen a manifest, a report, a book and e-mail, you name it.
Also interesting is the noun die Verfassung. It means constitution in sense of politics but it’s also used for the physical constitution in sense of the condition or momentary state of a person or a thing. The constitution is kind of the set up of a state, the condition is the (momentary) setup of a person, if you were wondering about a connection. 
der Verfasser – the author (less literary sounding alternative to “der Autor”)

• Ich verfasse einen Beschwerdebrief an die Vogue.
• I draw up/write a letter of complaint to Vogue magazine.

• Ich bin heute nicht in der Verfassung, trainieren zu gehen.
• Today, I’m in no condition to go and work out.

Let me know in the comments if you have any questions or if you want to try out some examples.