My fiancé and I have recently decided that we are going to start trying in a couple of months. And we are both really looking forward to it. And yet at the same time I'm a ball of nerves. It will be my first but he's done this before. Which can be handy so I have a steady rock somewhere. But any suggestions would be greatly appreciated.

My first suggestion would be to get married.

It would be a good idea to visit your doctor for a preconception visit to discuss your general health, any possible health issues that may influence a pregnancy, etc.. Also wise to start on a prenatal vitamin or multivitamin with folic acid. It is beneficial to have this going while trying to conceive as folic acid can protect against certain birth defects that occur very early in pregnancy.
Make an other changes (you and your fiance) that you know would be healthy and wise.

I've actually been on that type of multivitamin for over a year. Was told I wasn't getting enough out of what I was eating because I was eating so little. I was on a type of Adirral so I didn't have any appetite to eat.

Getting married would be a good first step. Although marriage is not a guarantee of happiness and stability, I think legitimacy is greatly underrated today.

I'm illegitimate. But we are going to be getting married. So the daddy will still be in the picture. It's the actually pregnancy and related physical stuff I'm asking about though not the moral part. Not that I don't appreciate it.

Ok, since you have now specifically asked that we ignore the legitimacy issue, I'll ignore that part of things.

A good first step is scheduling a pre-conception appointment with your doctor. He can go over all of the things you can do to give your pregnancy the best possible chance. A personal suggestion is to get to the weight and level of fitness that you'd like to attain post pregnancy. It's a lot easier to return to a weight that you were initially than it is to lose extra weight after you've been pregnant.

Also, bear in mind that your fiancé already has preconceived notions of how you should behave and choices you should make while pregnant since he's done this before. You might want to discuss expectations beforehand. For instance, if his previous partner was very active and didn't gain much weight but you do, there might be miscommunications or disappointments for both of you.

Good luck... with everything.

I think you should discuss child rearing techniques with him. He's done it before so he probably has his own set of ideas on how to raise a child. Knowing what page both of you are on is very important.