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human
Just focus on the idea.
A good mantra that worked for me is 'I love all living beings and I receive love from all living beings'. Just close your eyes for 30 minutes each day repeating this on your mind constantly, you WILL see what I mean. If you can try to really feel love towards all. You don't need more than 30 minutes but whenever you are absent minded and you aren't really thinking about anything important you can repeat it then too, it takes near zero effort. 
You can add god into the mantra however you like, like for example, 'I love god and all living beings and I receive love from god and all living beings' 
You don't even have to mention that you receive love, but it might open you up more to receiving, just a guess.
This doen't seem to be your main objective, but this will start manifesting love into your life in every aspect too, it's very noticeable.
gpt
As for how to really feel it, I guess you can imagine yourself hugging random people and trees and animals and your idea of god.
Hugging seems to be a very powerful symbol of affection, so it really makes it feel more endearing.