The best way to gain merits on bitcointalk is to make sure that you make all the necessary available contributions that can help other members get answers to their questions and also make contributions that help the forum to grow to the next expected end, this is because most merits sources and other forum members are mostly interested in what you can offer as in form of help and also build the reputation that earns your that trust and acceptance from other forum members.
That being said, merits are earned but not begged for so for that you should work to earn merits and not demand for it this way.
Most definitely there is no shortcut to earn merits in the forum rather the only means they will seem easy is why you have in the head (knowledge) to offer and how you can be a solution to forum users issues and equipment to satisfy the bitcointalk forum platform with good featuring insights of opinions.
You earn merits as rewards of your good offers and not my compassionate.