Grunge style knit sweater

[Salunyar]

Hi, I'm new here and have never knitted before. My mum said she would knit me a sweater if I suss out the pattern and gear for her. I'm wanting a grunge style light loose spacey raggedy knit pattern. Like this image attached (rodarte). I've looked around but haven't seen any patterns that create this look so am wondering if anyone can help point me to the right pattern?

Thanks in advance.

[Antares]

From looking at the picture, it looks like the ribbing was done with a "normal" size needle (i.e., one recommended by that yarn weight), but the rest of the sweater is done with extra large needles (maybe 17s, 19s, or even larger). Then it appears that in some places, a stitch or two was dropped and allowed to unravel for several rows (creating the