In my mind, a friendship is based on trust, mutual admiration, shared interests, and a shared history (which starts out as shared experiences). In making new friendships, it’s important to seek out people who are similar to you in some ways (like what they want out of a friendship) but could be very different in other ways (which will make the relationship more interesting). Usually, you can figure out if another person fits this description just by interacting with them. If not, you can ask a few careful questions, like, “What do you look for in a friend?” “Do you have expectations for yourself and the other person in a friendship?”
You may also have to negotiate how much time you’re expecting to put into a friendship. People with more friends will often want to devote less time to each individual friendship (and vice versa).
5. Practice the 51% rule.
This is something I learned from a friend at a church I went to in California. Every friendship will have some sort of give and take. In order to not make the friendship about figuring out how you can balance favors given with favors received, try to give a little bit more in the relationship (but not too much more, as then you might feel used). This is where the idea of 51% comes from. If both sides try to do this, then there is very little likelihood that one person will feel that they’re being taken advantage of in the friendship.
6. Purposefully do things together.
With all that as a foundation, here comes the most important step: Do stuff together. Remember that friendships are based on “trust, mutual admiration, shared interests, and a shared history” (quoting myself). Doing stuff together is where most of that happens. Even shared interests can be discovered as you do things together and talk. This usually needs to be something that you purposefully try to schedule or invite the other person to participate in. If not, it may not happen.
I like to invite people to go on walks, which is relaxing, a good opportunity for conversation, and good exercise. Other good options are: inviting people over to cook together, going out for coffee or meals together, playing games together, reading books concurrently and then discussing them. Usually, active things are better than passive things. E.g. cooking together may be better than going out for a meal together, because cooking is an endeavor that you can do as a team. But of course, both activities can be done at different times.
During this time of doing things together (and especially trying to schedule them and invite the other person to participate), you will see if the friendship is viable and whether it’s one that you want to invest time and effort in. It should be noted that friendships are not free. They require time, effort, and some money. This is something that needs to be considered. But if it is a good friendship, then it is often worth it.