´Asim bin Laqit bin Sabrah narrated:` From his father who said: "I said. 'O Messenger of Allah! Inform me about Wudu.' So he said: "Perform Wudu well, and go between the fingers, and perform Istinshaq extensively except when fasting."
Hadith Referenceسنن ترمذي / كتاب الصيام عن رسول الله صلى الله عليه وسلم / 788