I am a beginner with QGIS.
I have a raster aerial photo and wish to overlay a vector shapefile (I have already created) showing polygons of land use.
Can this be done in QGIS, or do I need to use photoshop?
If we assume that your vector layer is in the right projection and digitised correctly, then your raster must be georeferenced. In QGIS you will need to use the Georeferencer-plugin along with a map-service open (like Google Satellite) within QGIS map canvas. Now you go read the rest.