Don't pray standing in front (ahead) of the grave

رَوَى مُحَمَّدُ بْنُ أَحْمَدَ بْنِ دَاوُدَ عَنْ أَبِيهِ قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الْحِمْيَرِيُّ قَالَ كَتَبْتُ إِلَى الْفَقِيهِ ع أَسْأَلُهُ عَنِ الرَّجُلِ يَزُورُ قُبُورَ الْأَئِمَّةِ ع هَلْ يَجُوزُ لَهُ أَنْ يَسْجُدَ عَلَى الْقَبْرِ أَمْ لَا وَ هَلْ يَجُوزُ لِمَنْ صَلَّى عِنْدَ قُبُورِهِمْ أَنْ يَقُومَ وَرَاءَ الْقَبْرِ وَ يَجْعَلَ الْقَبْرَ قِبْلَةً وَ يَقُومَ عِنْدَ رَأْسِهِ وَ رِجْلَيْهِ وَ هَلْ يَجُوزُ أَنْ يَتَقَدَّمَ الْقَبْرَ وَ يُصَلِّيَ وَ يَجْعَلَهُ خَلْفَهُ أَمْ لَا فَأَجَابَ«» وَ قَرَأْتُ التَّوْقِيعَ وَ مِنْهُ نَسَخْتُ أَمَّا السُّجُودُ عَلَى الْقَبْرِ فَلَا يَجُوزُ فِي نَافِلَةٍ وَ لَا فَرِيضَةٍ وَ لَا زِيَارَةٍ بَلْ يَضَعُ خَدَّهُ الْأَيْمَنَ عَلَى الْقَبْرِ وَ أَمَّا الصَّلَاةُ فَإِنَّهَا خَلْفَهُ يَجْعَلُهُ الْأَمَامَ وَ لَا يَجُوزُ أَنْ يُصَلِّيَ بَيْنَ يَدَيْهِ لِأَنَّ الْإِمَامَ لَا يُتَقَدَّمُ وَ يُصَلِّي عَنْ يَمِينِهِ وَ شِمَالِهِ

Narrated to me Muhammad bin Ahmad bin Dawood, from his father, from Muhammad bin Abdillah Al-Himayri who said,

In a letter written to the Faqih [Imam Az Zaman (atfs)] a person asked the question,

[Question]: "A man goes for Ziyarah of the graves of the Imam's (as). Is it permitted or not that he prostrates upon/on the grave? And is it permitted that when praying near the graves of some of the Imam's (as) that he stands behind the grave and makes the grave (in the direction of) Qibla? Or stands near the head of the grave or near the leg of the grave? And is it permitted or not that he stands in front of the grave and prays and the grave if behind him?"

And he recited the letter [reply from the Imam (atfs)] from his copy:

[Answer]: "As for prostration upon the grave it is not permissible in naafilah prayers, obligatory prayers, and in ziyarah. And upon him is the act that he puts his right cheek on the grave. And as for the Prayers, keep the grave of the Imam in front and stand behind it. Its not permissible to pray Salaat in front of the grave because for the Imam (as) should not be advanced and pray on the left and right side of the grave."

[Source: Tahzeeb Al-Ahkam, Vol. 2, Pg. 228]

Same narration is present in Al-Ehtejaaj, Vol.2, Pg. 312 and quoted in Bihar Al-Anwar Vol. 53. Pg.165 . The words in that narration are:

ولا يجوز أن يصلي بين يديه ولا عن يمينه ولا عن يساره لان الامام لا يتقدم عليه ولا يساوي

"It is not permissible to pray Salaat in front of the grave and also not on the right side and left side, because the Imam (as) should not be advanced and should be at same/equal position."

Don't show your back to the Grave until you exit

Part of long narration from Imam Sadiq (as) teaching a Ziyarah of Imam Husain (as):

فإذا خرجت فلا تُوَلِّ وَجْهَك عن القبر حتّى تخرج

"When you leave, do not turn your face from the grave until you exit."

(This would mean do not show your back to the grave untill you exit)

[Source: Kamil Al-Ziyarat, Chapter. 84, Hadees. 2]

Saddened look on the face when going for Ziyarah of Imam Husain (as)

حدثني ابي واخي وعلي بن الحسين وغيرهم رحمهم الله، عن سعد بن عبد الله بن ابي خلف، عن احمد بن محمد بن عيسى الاشعري، عن علي بن الحكم، عن بعض أصحابنا، عن ابي عبد الله (عليه السلام)، قال: إذا أردت زيارة الحسين (عليه السلام) فزره وأنت كئيب حزين مكروب، شعث مغبر، جائع عطشان، فان الحسين قتل حزينا مكروبا شعثا مغبرا جائعا عطشانا، وسله الحوائج، وانصرف عنه ولا تتخذه وطنا

My father, my brother, Ali bin Husain and others all narrated to me from Sa'd ibn Abdillah ibn Abi Khalaf, from Ahmad bin Muhammad bin Isa Al-Ashari, from Ali bin Hakam, from some of our companions, who said:

Abu Abdillah Imam Sadiq (as) said,

"When you want to go to the Ziyarah of Husain (as), go to his Ziyarah while you are saddened, anguished, gried-stricken, disheveled, covered with dust, hungry and thirsty for verily Husain (as) was killed while He was saddened, anguished, disheveled, covered with dust, hungry and thirsty.Then ask him for your needs and then leave. Do not take it (karbala) as your homeland.

[Source: Kamil Al-Ziyarat, Chapter. 48, Hadees. 3]

Walk barefooted when going towards the Grave of Imam Husain (as)

وحدثني علي بن الحسين بن موسى بن بابويه وجماعة رحمهم الله، عن سعد بن عبد الله، عن الحسن بن علي بن عبد الله ابن المغيرة، عن العباس بن عامر، عن جابر المكفوف، عن ابي الصامت، قال: سمعت ابا عبد الله (عليه السلام) وهو يقول: من أتى قبر الحسين (عليه السلام) ماشيا كتب الله له بكل خطوة الف حسنة ومحا عنه الف سيئة ورفع له الف درجة. فإذا اتيت الفرات فاغتسل وعلق نعليك وامش حافيا، وامش مشي العبد الذليل، فإذا اتيت باب الحائر فكبر اربعا، ثم امش قليلا ثم كبر اربعا، ثم ائت رأسه فقف عليه فكبر اربعا وصل عنده، واسأل الله حاجتك

Ali bin Husain bin Musa bin Babawayh and a group narrate to me, from Sad bin Abdillah, from Hasan bin Ali bin Abdillah bin Mughirah, from Abbas bin Amir from Jabir Al-Makfoof, from Abu Samit who said:

I heard Aba Abdillah Imam Sadiq (as) say,

"Allah will register one thousand good deeds and erase one thousand bad deeds for every step taken by those who go to the Ziyarah of the grave of Husain (as) on foot. He will also increase their status one thousand times."

"When you arrive at the river Eupharets (furat), perform Ghusl, carry your shoes and walk barefooted like a humble slave. Once you arrive at the door of the Ha'ir recite Takbir four times. Then walk a little and repeat this four more times. Then approach the location close to His head, stand there and repeat it four more times. Establish prayers next to His grave and ask Allah (swt) for your needs."

[Source: Kamil Al-Ziyarat, Chapter. 49, Hadees. 4] 

Don't eat sweets and delicious food when in Karbala

حدثني ابي رحمه الله وعلي بن الحسين وجماعة مشايخي رحمهم الله، عن سعد بن عبد الله بن ابي خلف، عن احمد بن محمد بن عيسى، عن علي بن الحكم، عن بعض أصحابنا، قال: قال أبو عبد الله (عليه السلام): بلغني ان قوما إذا زاروا الحسين (عليه السلام) حملوا معهم السفر فيها الحلاوة والاخبصة وأشباهها، ولو زاروا قبور أحبائهم ما حملوا معهم هذا

Narrated that Abu Abd-Allah Imam Sadiq (عليه السلام) said,

"I have been informed that some people go to the Ziyarah of Husain (عليه السلام) carrying different kinds of food with them, including sweet and Akhbisah (a type of desert) and other similar deserts. Verily if they had gone to the graves of their loved ones, they would not have taken any of these things with them.

[Source: Kamil Al-Ziyarat, Chapter. 47, Hadees. 1]  

 حدثني محمد بن أحمد بن الحسين، قال: حدثني الحسن ابن علي بن مهزيار، عن أبيه، عن الحسين بن سعيد، عن زرعة بن محمد الحضرمي، عن المفضل بن عمر، قال: قال أبو عبد الله (عليه السلام): تزورون خير من أن لا تزورون ولا تزورون خير من أن تزورون، قال: قلت: قطعت ظهري، قال: تالله ان أحدكم ليذهب إلى قبر أبيه كئيبا حزينا، وتأتونه أنتم بالسفر، كلا حتى تأتونه شعثا غبرا

Narrated that Abu Abd-Allah Imam Sadiq (عليه السلام) said,

"Your going for Ziyarat (Imam Husain عليه السلام) is better than not going and your not going for Ziyarat is better than your going."

The narrator said, "You have broken my back (confused me?)."

Imam (عليه السلام) said, "By Allah,  when one of go to the graves of your fathers you are distressed/sad and mournful. But when you go to Imam Husain (a.s.) you carry different foods. It is better not to go, unless you come to Him with disvelved hair covered in dust."

[Source: Kamil Al-Ziyarat, Chapter. 47, Hadees. 4]  

From a Ziyarat of Imam Husain (عليه السلام) as taugh by Imam Sadiq (عليه السلام):

ولا تدَّهِن ولا تكتحل حتّى تأتي الفرات ، وأقلَّ الكلام والمزاح ، وأكثر مِن ذكر الله تعالى ، وإيّاك والمِراح والخصومة 

"And do not apply oils or kohl until you come to the Euphrates (furat), and talk less and joke less, and remember Allah (تعالى) more, and beware of being jolly/chearful and quarrelling."

ثم تأتي النينوى فتضع رحلك بها، ولا تدهن ولا تكتحل ولا تأكل اللحم ما دمت مقيما بها 

"Then enter Nainawa and put down your luggage there. Do not use any oils or kohl and do not eat meat as long as you stay there."

[Source: Kamil Al-Ziyarat, Pg. 238-239]