What are some of the best things I can do or take to help myself conceive? Kinda desperate, please help me!

I'm 22, my fiancè is 25, and our daughter will turn 2 years old on April 8th. Here's my dilemma.. I've always wanted my kids close in age because my only blood sibling is 14 years younger than me, and that obviously caused us not to be as close as I wanted, because i had to go to big girl things once I turned 18. My second dilemma is that it seemed extremely hard for me to get pregnant and carry my daughter as far as I was able to, in the first place. I had 2 miscarriages before my daughter, and I've had one more in this past year. My fiancè was gracious enough to come into mine and my daughter's life just a little bit after my daughter turned a year old, and from day one he took my daughter in as his own and he will be signing the papers to adopt her very soon♡ I want to show my fiancè the joys of that first year with a newborn, because he hasn't gotten to

experience those joys yet..♡