The best type is the helpful type (in my opinion). Make posts that are related to the subject matter of the thread. Offer some value in your response and provide assistance if you can.
The best forum of forum posting is where you provide value in your posts. Helping the people that asked the question in solving a problem or just asking for advice.
Well, people use forums to discuss various things. Generally, they have an issue or a question that they want to resolve/answer. With this in mind, be sure to look for forums/posts that are related to topics that you have some knowledge about and do your best to assist with the question/problem being addressed. The whole point is to either post regarding a question or problem you are facing, or help someone solve/answer their question/problem.
The right and the best way for posting on forums that don`t look at forum links only from the "backlinks" perspective. Keep in mind that there is a real person behind every nickname and this person may become your potential costumer
Forum is the best way to get back link to your website and engage with lot of unknown people, it is also a great place to help others. Post on your same category forum is the best to work on forum link building
I think forums are great to share information with others and to ask questions. I remember back in 2006 when I was new. I loved it when someone would share information with others that were new and learning their way. Whenever I hear of updates to various affiliate programs or an MLM I may be in if I find out new information I like to share it with others regardless of whether people are all in the same lineage. Sometimes on forums (not this one) I see people just continually trying to promote themselves but never have anything of any value in their posts. Then you also see people who are very negative about working online in general that just go to forums to try and upset folks. This forum is the best one I have ever seen for being polite and respectful of others while still conveying ones own opinion.
The best way, in my opinion is to post so that you can position yourself as an expert. If someone needs more help than the forum can help with they can ask for that extra help from you through the forum or they can find you on a google search but it starts, I believe as moving from one level towards becoming that expert in your niche. They might look to see how much knowledge you have. Maybe if you're answering a lot of questions that are good, that too. They will look you up. First they may think you are an expert then they learn more and begin to know you are the expert when you become one. It's not that hard. If you want to take you and your niche that far. Also find posts for question on the same day. I answer this one because I like this topic but find posts that are just out, and answer them. Get better and learn more about the question (most people in a niche have the same questions) and answer the next related question. As you learn you'll get better and better. If someone posted 90 days ago, they have probably found the answer or they don't have that problem anymore. So answer questions that are new. Now you kind of have to decide, in my opinion, if you want to even do forums. Because you'll want to spend all your time there to grow and see if it's worth it to you. Maybe your best traffic comes from somewhere else. Maybe not. If you want to do forums, go all out for 90 days just doing what I talked about. Your credibility will be high after learning more on your niche. The answers have to be close to the best or the best on that topic. Place a link to your highest credibility place you have online and see what happens. Whatever you do, If you're doing this to generate income don't spend quality time in forums if you're not willing to grow and learn to be good at helping a certain niche get results. If you would, I would suggest go all out and answer the questions you know are great answers and get started. You can also do a google search and find more forums and do 20 minutes a day of answering questions. Find which work for you and if you enjoy it. You've gotta love it and it has to eventually work for what ever you want the answers to do for you. For me that is the best forum posting for generating income, if that's what you want it for. You can also use these tactics for a hobby. There are many more strategies to become successful in forums though. You might find them online if you do a search and spend some time on it. But It's up to you and good luck ! P. S. Remember that backlinks dont really matter anymore. Credibility for trust does.