How to get proper round shape Truffles

Hi All,I m new to this group and glad that I have joined it as mant at times one might have doubts or queries to share and discuss but there was no forum to discuss it.I'm a Chocolatier from Bangalore and recently I had made it as my profession. Just one problem which m facing is m not able to get that proper round shaped Truffles, some or the other way they become distorted even after using the tools.I basically dip it in the chocolate and take out with fork. But after 5 or 6 the chocolate starts becoming harder.Is there any other way of doing it or do we have any molds for round shape truffles.TIA