I can't find a hadith that deals specifically with this situation. But Here are some hints I learned from scholars that talks about Waking up for Fajir.
I already have summarized them down because sometimes I too struggle to wake up. Let me share it here.
The 1st and most important reason that can help you wake up for Fajir is your Niyah. you solely wish to wake you for fajir just for his sake and not someone's else sake. If you are honest with allah about your need to wake up for Fajir he would definitely help you wake up. However to get his help you need other things that come with the Niyah. Scholars call it: (الأسباب) which may means ways
Without any delays, Ingredients are:
1- Alarm to wake you up. Nowadays they sell flying Alarms. The only way to turn it off is to climb. Amazon link here
2- Sleep early. Can't emphasize more on this point. If from your experience you know if you sleep after this specific hour that you will not be able to wake up for Fajir, the scholars said it is haram for you to stay late until that hour. For example, If you know if you sleep after 12 you will not be able to wake up. Then it is haram to stay awake after 12.
3- Dua'a, Dua'a, and Dua'a(supplications). Make Alot of Dua'a that allah can help you wake up for fajir. Again, depends on your Niyah. How honest you are in your Dua'a, how much allah will help.
4- If you know someone who wakes up for Fajir, tell him to come and wake you up. knock on your door. tell him to call you, or even tight a robe on your legs throw it through the window and let him pull it when he is nearby.
5- Read the Athkar before you go to sleep. You can find these Athkar Here or in this youtube video also if possible make wudu.
6- The last one which many people don't pay attention to is YOUR SINS
Fajir prayer is actually a meter or a gauge that shows how much Imaan(Faith) you have. If you implement the ways mentioned above and you still miss Fajir. This definitely means your sins are holding you from waking up. if you think you are not doing any sin, then I higlhy suggest that you Search deep in your soul. You don't know one day you looked at a something you were not supposed to look at, you miss treating your parents, you didn't call your relatives since along time, you backbite and you think it is not backbiting, or even that you prayed Fajir once and that gave you a feeling in which you think you are better than those not praying Fajir(not being humble). . You should now your soul very well. There is a sin in there you didn't take notice of it.
Let me end this point with this story,
A man said to 'al-Hasan al-Basri': "O 'Abu Sa’eed', I sleep in good health, and I love to pray qiyaam al-layl(Night prayer), and I prepare water with which to purify myself, so why can I not get up?" 'Al-Hasan' said: "Your sins are restricting you.” He said, may Allaah have mercy on him, "The slave who commits a sin will be denied the opportunity to pray qiyaam at night and to fast during the day."
If after taking all these ways you still weren't able to wake up becaus you are a heavy sleeper then:
It was narrated that Abu Sa’eed al-Khudri (may Allaah be pleased with him) said: A woman came to the Prophet (peace and blessings of Allaah be upon him) when we were with him and said: “O Messenger of Allaah, my husband Safwaan ibn al-Mu’attal does not pray Fajr until the sun has risen.” Safwaan was with him, so he asked him about what she had said, and he said: “O Messenger of Allaah, we are a family who are known not to wake up until the sun has risen." He said: "When you wake up, then pray."
Narrated by Abu Dawood, 2459; classed as saheeh by Shaykh al-Albaani in Irwa’ al-Ghaleel, 7/65
Source of this - IslamQA
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