Im making a lalaloopsy cake for my daughters 4th birthday in a few weeks. Can anyone tell me if its better to use gum paste or fondant to do a doll sculpture and how long in advance can I make it and store until im ready to put it on the cake?

My daughters love Lalaloopsy!!  I don't know which would be better...probably fondant as gumpaste tends to get really hard.  In my experience (and I don't have a lot, so please take this with a grain of salt), the gumpaste also cracks a little bit, whereas the fondant tends to stay smooth looking.  I've made decorations up to a week in advance out of fondant and they held up just fine. 

But perhaps someone with more experience can weigh in for you.  Good luck!!  I give you props for taking on the task of making the doll yourself!! 

AWhen I make figures in advance, I do the basic shape in gumpaste and cover it in fondant. I think its easier to "dress" it that way, plus the fondant stays in place better. But with that being said, I use marshmallow fondant so its a softer texture than regular fondant.

Acarrascoshannon, thank you! it means more to me to do it myself. I do plan to use marshmallow fondant. I hear the taste is way better than the store bought kind. Thank you for your advice threefifty!!

AIn my opinion, store bought has a bitter taste, whereas marshmallow fondant literally tastes like marshmallows. That's all I'll use!!

Oh quick tip, right after you melt the marshmallows, but the coloring in BEFORE you add in the powdered sugar. It's sooo much easier than trying to kneed it in after its made.

For my figures, I use a mix of both fondant & gumpaste.   That is how I made these http://cakecentral.com/g/i/2346582/a/2347582

You can actually make it weeks in advance.  I didn't have much notice from my niece for this one so I actually made them a few days before.

Goreti...those are ADORABLE!!!  I really need to step up my game :P 

Good luck with the cake endeavor, OP!!!  Can't wait to see how it turns out :)

Thank you so much! I was wondering about that!

Ok I'll try that! What is the gum paste to fondant ratio?

I'd say about 50/50.  By adding the fondant, it will give you more time to play with it before it dries.

I see a lot of you are using marshmallow fondant... I  have made a few batches, any advice on recipes and and tips you could give me would be greatly appreciated?!?!  I am new to this fondant stuff... Thanks :)

This may help - they used gumpaste.

http://artisticakesflibbys.blogspot.com.au/2013/01/lala-loopsy-gumpaste-figure-tutorial.html

When I make figures i just use gumpast because when i use fondant they start to look like they are melting :( .

I just use the regular cake decorating icing.  The fondant looks nice, but taste awful. I haven't made any using the fondant that the customer didn't said they would go with the butter cream icing in the future.   I go for the taste over the looks any day and get lots of complments on my cakes.  You can cook your cake and wrap it in plastic wrap and freeze it for as long as you want.  I usually decorate it a day before.  The cake is sooo moist and the icing is delicious.