Form away. This is up to you and your skill level. If you have a wheel, great. If you don't, there are ways around that. If you're brand new to pottery, seek out a professional or watch a few videos online; it's an art that requires skill, most definitely.
Some clays aren't able to be molded, shaped back into a ball, and molded again. So when you make your choices, be careful -- your clay may not be too keen on giving you a second chance.