People in an FWB arrangement are firstly friends
Just like any friendships, people in friends with benefits relationship are 2 friends who enjoy each other's company. They care about each other and back each other up when in need. Sharing each other's problems to relieve themselves of the stress that life throws at them and importantly have fun! The added term "with benefits" just removes any intimate developments that may arise within the relationship. But there are certain rules that people follow to make these relationships last and work out.
How is it Beneficial
People are skeptical of a friendship that consists of sex, as it becomes complicated. But many people find solace in such relationships. Such as divorcee's who have trouble putting their faith in love, can have such relationships without worry. People who enjoy sexual intimacy can engage in friends with benefits dating for satisfying their needs. This relationship status is one in which 'moving on' isn't as hard. Since both friends are aware that it is mainly a sex-based relationship and no deep intimate feelings are to be harbored by the latter.
How to keep the relationship healthy?
Keeping this sort of bond healthy is a bit different. From the start of the relationship, both partners should agree on a physical-attraction relationship since most people don't consider FWB's like an actual friend, rather just a sex buddy. Because any emotional build up will cause confusion and pain for both partners.
Try to keep communicating with each other to a minimum. Like wishing them happy birthday won't hurt or asking them to hangout once in a while. But don't text them just to talk or asking them out too frequently, since you may start to depend on them, also causing you to be offended when they can't make it.
Be cautious of criticism from people. Don't let it affect your plans, since people succumb to criticism and start to doubt themselves, stay strong. If you do end up falling for your FWB, break it off, as your partner won't harbor feelings for you since they never intended on developing feelings from the start.
Who should and shouldn't adapt an FWB status
Not everyone can throw themselves into Friends With Benefits status, we're all different after all. People with certain traits should avoid being in this type of status, such as one's who tend to get jealous very easily since they develop negative thoughts. If you think that having sexual intercourse is what love is all about then you're probably not going to be aware of FWB either. Succumb to partners who make you have a good time under the sheets, then avoid this type of relationship.
People who succeed in retaining this relationship tend to have a joyful life. This isn't for everyone but most have stated they remained happy, some even reject marriage and spend their time with their Friends With Benefits. So, to each their own way of enjoying their bond with their friend with benefits.