How to do this?

I manually made a mesh. I tried reducing the mesh in grasshopper. That did not give a result. I also tried making the original mesh a simple mesh because I had converted a surface to a mesh so it was very messy. Can someone suggest a way of doing this? Just wanted to know. 

I got this as a result. 

just need a hint.

no need to say I am not very good at it. only a hint.