[وَاسْتَعِينُواْ بِالصَّبْرِ وَالصَّلَوةِ وَإِنَّهَا لَكَبِيرَةٌ إِلاَّ عَلَى الْخَـشِعِينَ - الَّذِينَ يَظُنُّونَ أَنَّهُم مُّلَـقُوا رَبِّهِمْ وَأَنَّهُمْ إِلَيْهِ رَجِعُونَ ]
(45. And seek help in patience and As-Salat (the prayer) and truly, it is extremely heavy and hard except for Al-Khashi`in.) (46 (They are those) who are certain that they are going to meet their Lord, and that unto Him they are going to return.)
Muqatil bin Hayan said that this Ayah means, "Utilize patience and the obligatory prayer in seeking the Hereafter. As for patience (here), they say that it means fasting.'' There are similar texts reported from Mujahid.
We can either fast the 13th ,14th, and 15th of Every Islamic Month
or on Mondays and Thursdays as the Prophet (Saw) did.
But You should fast At least 3 days a month because that is what companions did.
For more about fasting: http://islamqa.com/en/ref/
As Far as Qiyaam goes:
Verily, your Lord knows that you do stand (to pray at night) a little less than two thirds of the night, or half the night, or a third of the night, and also a party of those with you. And Allah measures the night and the day. He knows that you are unable to pray the whole night, so He has turned to you (in mercy). So, recite you of the Qur'an as much as may be easy for you . He knows that there will be some among you sick, others travelling through the land, seeking of Allah's Bounty, yet others fighting in Allah's Cause. So recite as much of the Qur'an as may be easy (for you).
(end of surah Muzzammil)
We may not be able to pray half the night, but we CAN recite as much Quran as is easy for us inshaAllah.
This is an important Sunnah that we should not forget.
Yahyaa ibn Mu’aadh said: “The medicine of the heart is five things: reading Qur’aan and pondering the meaning, having an empty stomach, praying at night (qiyaam al-layl), beseeching Allaah at the time of suhoor, and keeping company with righteous people.”
Muhammad ibn al-Munkadir said: “There is nothing left of the joys of this life except three: qiyaam al-layl, meeting one’s brothers in faith, and praying in congregation.”
Yazeed al-Riqaashi said: “A lot of tahajjud brings delight to the worshippers, and a lot of thirst (i.e., fasting), brings joy when they meet Allaah.”
"Dont hope for satisfaction and pleasure in food and the desires of this life. We are travellers, these
comforts are not everlasting, our Destination is the next life, where the pleasures are complete
Rather hope for comfort in the word of the Most Merciful, in Standing in front of Him, the Loving, alone at night, prostrating to Him, while the world sleeps."
Here is a link with tips
Then he (Saw) said: "Shall I not guide you to the gates of goodness? Fasting is a shield; charity extinguishes sin as water extinguishes fire; and a man's prayer in the middle of the night." Then he recited: "Who forsake their beds to cry unto their Lord in fear and hope, and spend of that We have bestowed on them. No soul knoweth what is kept hid for them of joy, as a reward for what they used to do". [Qu'ran, Surah al-Sajdah (32): Ayah 16-17] -from hadith 29 of the 40 hadith
‘Abd-Allaah ibn Mas’ood (may Allaah be pleased with him) narrated, “We were young men with the Prophet (peace and blessings of Allaah be upon him) and we did not have anything (i.e., we could not afford to get married). The Messenger of Allaah (peace and blessings of Allaah be upon him) said to us, ‘O young men, whoever among you can afford to get married, then let him do so, for it is more effective in lowering the gaze and guarding chastity. And whoever is not able to do that, then let him fast, for that will be a shield for him.’” (al-Bukhaari, 5066; Muslim, 1400). Fasting reduces the effects that desires have on young people.
"Allah the Almighty has said: 'Whosoever acts with enmity towards a closer servant of Mine (wali), I will indeed declare war against him. Nothing endears My servant to Me than doing of what I have made obligatory upon him to do. And My servant continues to draw nearer to Me with supererogatory (nawafil) prayers so that I shall love him. When I love him, I shall be his hearing with which he shall hear, his sight with which he shall see, his hands with which he shall hold, and his feet with which he shall walk. And if he asks (something) of Me, I shall surely give it to him, and if he takes refuge in Me, I shall certainly grant him it.'"
And Allah (swt) knows best