One of your goals of your placement will be to produce evidence of your development over the year. These can be in the form of a signed off record of work by your manager. The starting point is to be able to write the record in such a way that accurately decribes your achievements. You could use the STAR technique describing:
Situation - How, where, when and with whom did you gain the experience?
Task - Describe the tasks you undertook
Action - What actions did you take to complete the tasks?
Result - What results did YOU achieve?
If you keep this acroymn in mind during you year you find it easy to record your results in a way lets people who read it understand your skills and competencies acquired. Your Year in Industry is not all about 'Tecnical Stuff' as you will need to develop other areas as well.