I agree with @breloya, if you're willing and want to do it but its just not the right time for you, just let her know. If its something you're uncomfortable doing, stick by your decision

Being pregnant now I'm not sure how surrogate moms do it. I feel so close to the baby during pregnancy that the idea of having them and then sending them home with someone else sounds similar to having my heart ripped out. I don't think I'm strong enough to handle that. Surrogacy is more than just the time and toll on your body. It definitely isn't for everyone.

It's a huge commitment. Don't feel bad. I used to want to carry for another, but now, I won't be another woman's surrogate. It's a lovely thing to do for someone else, but after each birth, I lost far too much blood and I'm not trying to die and leave my own kids behind. We all have our reasons for why we will do or not do something. Pregnancy is a big deal and is rough on our bodies as is. It's a lot to ask of someone else. Don't feel guilty for saying no. Now, if you want to help her, but don't simply because of how short ago you just gave birth, tell her you're willing in a year or whenever. If you just don't want to at all, own that "no" and keep it moving. Pregnancy is hard and just because you can have a baby and just because she's your friend, it doesn't mean you're obligated to carry for her. I hope nothing I've said has come off as too harsh.

Aww I was thinking about doing this for my sister but we are looking into home insemination are something