For me it was by horses I bought. I started out with a racehorse and a broodmare. My one race horse did pretty weel which helped, but I ended up seeling him. My stable is still getting big, but what helped me was when I bought my stud Native Justice. He won four graded stakes races and got me over a mil in profit and from there iw as able to get better horses and such. Also leasing a few good horses helped too.