How do I get someone to take my LSAT for me?

I am studying LSAT, and it is extremely difficult to be consistent with my studying routine. There are other days when I am totally demotivated, and that is showing in my progress. What are some of your motivational strategies and concentration tools when preparing to take the LSAT? Also, I have heard of services that promise to take my LSAT test for me exam in my place, but what I am wondering is what the ethics and practicality of it are, have they been used them and is there not a better way to keep up with the field?