I need help with my data mining project

Hello guys,
so im working on a data mining project and i need ur help .
i have a data of a 5000 customers for a bank
9% of them have took a personal loan
now i want to build a decision tree classifier and find out what are the similarities between the customer who have took the loan
and find the list of customer who have a higher probability of taking the loan .
can someone help me with this ? what are the steps of doing this ?