To be this kind of person first we need to see the positive side of people and things as well. And to be in this mindset we must practice observing and not only see or else we might not see and understand the good side of acts done by other people.
A positive mindset can only be motivated by others, those who see opportunity and chance in something which doesn’t even seem to be in favor at times.
When we see someone doing something which we also wish to do but are unable to do due to different circumstances, we feel motivated and inspired to work more and learn more so we could help others like we see one doing. In some cases, we only feel happy because someone else is helping others or supporting others, and when it comes to us helping and supporting someone then we feel burdened or we say why should I? stay away from this kind of mindset or thoughts which will make you a pathetic personality and then you will act as a selfish being, which is of no use when we all have limited time to live and do things for us and others as well.
For ref: Psychology of Money
Genuine people have vibes even when they don’t say anything they are able to spread positivity and happy vibes with others. So, when you are with someone who is happy and contented inside out you will be inspired and motivated to be the same, you just have to feel this by being with someone who doesn’t have anything to take but just to offer.
Stay away from any kind of judgments and thoughts about other's behavior or life, this stops you from learning things from others, we all very well know that everyone has something to teach, so be open to grab that, and never lose a chance to learn something which you are not aware of.
If you have any suggestions let me know...