How Do I Stop a Tantrum?

Two year old has big emotions. She will lose it quicker than most. How do I positively reassure her that she can feed herself with a spoon or clean up if mum or I aren't in the space? And how do I get her in her car seat or stroller without having to bribe or risk an epic meltdown  that ends the only option of being overpowering her into the car prams her?