Don't just make du'a during these 10 days, especially on the day of Arafah. Give charity too in words and kindness. Follow up your du'a with Sadaqah Al-Imām Wahb ibn Munabbih, said: “The likeness of someone who supplicates without performing good deeds is like someone who shoots an arrow without a bow - [i.e., a futile endeavour].” Kitāb az-Zuhd, 2187 | Al-Imām Ahmad bin Hambal]