In addition to those two methods, there is also one other way to increase affection. After the summer holidays are over, you can talk to the old man at the mansion and spend time with him. This is the only way to increase affection for free.
Oh I didnt know that one ^^ I'll think about it on my next game, thanks ^^
There's one more! If you solve the kindergarten teacher's problem, you can work as part-time teacher. It also increases your affection a little.
