ANSWER:

No need to go out and come back in. 

Simply say bismillah in your heart and make wudu. Saying bismillah before making wudu is not mandatory though.

Wudu after answering the call of nature: before urinating I say the dua. After finishing if I want to make wudu, do I have to leave the bathroom say ghafranka and say bismillah and enter again to do wudu? Or can I just continue making wudu in the bathroom after urinating.

Ablution (Wudhu) | July 17, 2021 12:43 am
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Is it allowed to apply nail mehandi stains that is made by burning sugar/ jaggery/tea leaves and the evaporated liquid is collected and applied? It won’t peel off it just colours the nails.so will wudu be valid?
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You said its not permissible to make wudu during menses, so can we recite the daily dhikr, recite the quran and make dua without wudu?