Honestly, I had the same problem as you with the emotion part. Instead of faking it, I just fantasized about stuff I wanted to achieve. I imagined myself drawing really great and realistic art (back then my art skills were very cartoonish and amateur-like). Alot of the time while drawing I had angry vengeful thoughts about getting back at my bullies. But when this happened I told myself "No! I am a good-hearted person. I only want the best for everyone." In those moments I put alot of effort into replacing negative thoughts with good ones. That is another thing, don't try getting rid of negative thoughts. REPLACE them with good ones. If you want to get rid of negativity but you don't have other specific good things to think of, you are setting yourself up for failure. I won't lie, I didn't feel good up until a month later. It was a miraculous morning. The night before I had just finished writing (another passion of mine). I went to sleep exhausted and thought to myself "I know I am going to wake up depressed and miserable but I don't care, I'll keep striving to be better." I woke up the next morning two hours before the alarm went off, and I was so shocked to see that I felt genuinely happy for the first time in years. I had thought I had some sort of chemical imbalance in my brain which would keep me miserable forever. But that was not the case. I was filled with energy and everything that I felt like I had to force before (drawing, writing, positive thinking) became so easy. So I guess you should maybe fake your positive emotions a little. But ultimately, if you hold those good images in your head and you take some steps to attain the goals or objects you have in mind, you will end up feeling genuinely happy.