So the assessment size is just smaller than A3 and we were asked to apply a bleed to show the cutting marks where it's smaller than A3.
The problem is that I've made and finished my poster to be the exact size required for the assignment - therefore there is no allowance for the bleed line (I hand drew it and scanned it into Photoshop)
MY QUESTION IS; would it look weird if I made the bleed lines sit outside along the posters edge? Everyone keeps telling me it's supposed to be on the image, or else well it's literally useless.
An image must go to the BleedBox and the TrimBox must be inside the design. The bleed adds several mm which are cut away in the final process. If your image stops at the trimm edge you will have problems inaccuracy when the paper is trimmed.
There is no need to print or to show bleed or trimm lines. This information is included in the PDF. You can make it visible in Acrobat's Preferences > Page Display > Show Art, Trim and Bleed Boxes.