your question is quite broad, but basically you have to edit the flamestrike model by scaling it bigger in a modeling program. And, i wouldn't buy 3ds unless you have a ton of cash or are planning to start a business because i heard its really expensive. I would get gmax (made by the same company as 3ds) because its free and has no trial time. You can also get milkshape (easier to use for beginners) but you can only use it for 30 days before paying. And how to do it, well go search for tutorials, there are many good ones out there.