There are two types of ladies who want twins. The crazies and those who have lost their children.
Those of us that have lost twins before birth desperately want a second chance to be a mother of living, intact multiples. Here is a little information on that how to get pregnant with twins again. It could be quackery. I fully acknowledge that. But it could also be helpful.
I have been told that increased folic acid, eating yam skins, flax seed oil, and nursing while conceiving increase your chances of twins. I'm going to give you a few other possibly quackery sites. Take them with a grain of salt or don't. By the way, clomid does not increase your chance of multiples if you have no fertility problems.
Odds of Twins
Identical twins can happen to anyone. Each pregnancy has a 1 in 250 chance of splitting and becoming twins. Fraternal twins are hereditary and run on the mother's side. The female must drop 2 eggs during a cycle to get pregnant with fraternal twins. The father's history has nothing to do with your chances of having twins.
Please know that twin pregnancies are VERY hard. Doctors who assist women in getting pregnant work very hard to ensure they carry only one child for this very reason. Identicals are even worse. The egg does not always split evenly which results in congenital defects or even one baby having cysts instead of organs. Most twins don't make it to term and a lot of children are raised without their twin sibling. There is mandatory bedrest and other minor complications. The risk of death continues until you take those 2 babies home and most of these little ones will spend some time in the NICU. Do not take this decision lightly.