I spontaneously picked up my first tent dress in the sale last year. Fits at the top, but I didn't realise how much material it has! Can I take it in a bit? With very little sewing knowledge 
I've added a couple of (sewing machine) darts in the front, which have pulled it in a bit & it looks better. But there's tons more at the back that needs more than a couple of darts. Is it even possible? Back in photo.
Added bonus. It has pockets! 
Can anyone patient help? In simple language, as my brain & energy are pretty low. Autoimmune nonsense.