ANSWER:

The intention is in your heart.

The niyyah is in the beginning, it suffices for the last rakah as well when you pray witr in 3 rakahs. 

https://youtu.be/5CdtuEE86Fw

When I pray Witr ( after praying Isha) Do I have to pray one or three rakats?If three Rakats , I need to start stating my intention for two times? First two rakats and then one rakat.

Prayer | November 24, 2018 4:41 am
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Sheikh is it necessary to say your intention by heart or verbally before doing wudhu in ghusl?