(The Messenger of Allah (PBUH) used to strive more in worship during Ramadan than he strove in any other time of the year; and he would devote himself more (in the worship of Allah) in the last ten nights of Ramadan than he strove in earlier part of the month.)

[Muslim]

It is recommended to remember Allah the Almighty abundantly during these ten days especially Tasbeeh (glorification), Takbeer (Exclaiming Allah is Great), Tahleel (the exclamation 'La ilaha illa Allah') and Tahmeed (praising Allah). Allah the Almighty says:

﴾Wealth and children are the adornment of the life of this world. But the good righteous deeds (five compulsory prayers, deeds of Allah’s obedience, good and nice talk, remembrance of Allah with glorification, praises and thanks, etc.), that last, are better with your Lord for rewards and better in respect of hope. ﴿ 

[Al-Kahf, 46]

The good righteous deeds (Al-Baqiyat As-Salihat) are Subhan Allah, Al-Hamdulillah, La Ilaha illa Allah and Allahu Akbar. When you glorify Allah, praise Him, bear witness that there is no deity worthy of worship but Allah Alone and exclaim He is the Greatest, you know Him then, and when you know Him, you obey Him, and upon obeying Him, you will gain happiness in this world and the Hereafter.

(O son of Adam! Seek Me and you will find Me. When you find Me, you will find everything else, but if you turn away from Me, you will miss everything else, and I should be the most beloved to you.)

These ten days are the best days in life, and thus we should remember Allah the Almighty abundantly through Tasbeeh, Takbeer, Tahleel and Tahmeed.