I recognise your problem, since I have experienced it myself. I wanted to have wings as well, but they didn’t seem to grow. It’s not ridiculous, I have flown ‘on normal ways’ but never with wings and I really want it too. After I had the fail attempt I made a list how to get wings. Some people helped me with the list 
- I could walk trough a door with ‘wings’ on it. If I’ve been trough the door I have wings.
- Spin around and imagine I will have wings.
- Fly normally and just imagine I have wings and know they will appear then
- ”Abracadrabra wings!” and point to my back. This was similar to what I did it the last dream though.
- Jump from a cloud. I have to get there first though, but I could do that by flying normally. I never had a problem with normal flying.
- Look what I’ve got in my pocket to see what could help. For example a ring or powder that will make them grow.
- Actually feel they’re coming out the back of me. Maybe that’s something I missed in doing, I didn’t really feel it I just though it.
- Take a pill - or any other food - that will give me wings.
Yet I think Bruno and Bright_Eyes_Rock mentioned the key point. If you read those options, you still need your visualization to make it work. This are only ways to help you to achieve the visualization better.
Good luck and let me hear when you try but fail or succeed to have wings.