The best thing which is recommended by traditions of masoomeen a.s. is to give sadaqa and do isteghfaar as much as possible.

For resolution of financial problems there are a lot of supplications and Ama'al recommended by masoomeen and our Ulama and some of them are experienced by Ulama and a large number of momeneen. Like you can rectite this zikr after fajr 100 times "Ya Wahhabu" and you should recite 27 times verse no. 58 of Surah Zariyat إِنَّ اللَّـهَ هُوَ الرَّزَّاقُ ذُو الْقُوَّةِ الْمَتِينُ after Fajr prayer as well.