Learn the deen more and advise them as best as you can. Dawah comes with knowledge, even if it were a little bit. Remember, the best form of calling people to Islam is through your own character and behavior.

Sheikh, i hv problem talking to people about islam. The most i can do is doa for those people i see around me to get guidance from Allah swt. My knowledge is limited and i have this guilty sad feeling in me for not being able to do more. Pls advise