From an older article at the Hudson Institute, with a very thorough description of how one becomes a Muslim Brother or a Salafi:
First, the Brotherhood uses a rigid process of internal promotion to ensure its members’ commitment to the gama’a and its cause. The process begins at recruitment, when specially designated Muslim Brothers scout out potential members at mosques and universities across Egypt. During the process of recruitment, prospective Muslim Brothers are introduced to the organization through social activities, such as sports and camping, which give the Brotherhood an opportunity to further assess each recruit’s personality and confirm his piety. If the recruit satisfies local Brotherhood leaders, he begins a rigorous five-to-eight-year process of internal promotion, during which he ascends through four different membership ranks, muhib, muayyad, muntasib and muntazim before finally achieving the status of ach ‘amal, or “active brother.”
During each stage of internal promotion, the rising Muslim Brother’s curriculum intensifies, and he is tested, either orally or through a written exam, before advancing to the next stage. For example, a muayyad (second stage) is expected to memorize major sections of the Qur’an and study the writings of Brotherhood founder al-Banna, while a muntasib (third stage) studies hadith and Qur’anic exegesis. Rising Muslim Brothers also assume more responsibilities within the organization: muayyads are trained to preach in mosques and recruit other members, and muntasibs continue these activities while also donating six-to-eight percent of their income to the organization.[11] This process serves to weed out those who are either less committed to the organization, or who dissent with some of its principles or approaches. Muslim Brothers’ commitment to the organization is further established through their assumption of a bay’a, an oath, to “listen and obey,” which occurs sometime after the midpoint of this promotional process.[12]
Second, the Brotherhood pursues its Islamizing project by maintaining a well-developed nationwide hierarchical organization. At the top of this structure is the Guidance Office (maktab al-irshad), a twenty-member body largely comprised of individuals in their late fifties to early seventies. The Guidance Office executes decisions on which the 120-member Shura committee (magles al-shura al-‘amm) votes, and orders are sent down the following chain of command: the Guidance Offices calls leaders in each regional sector (qita’), who transmit the order to leaders in each governorate (muhafaza), who pass it on to their deputies in each subsidiary area (muntaqa), who refer it to the chiefs in each subsidiary populace (shu’aba), who then call the heads of the Brotherhood’s local cells, known as usras, or “families.” The usra is typically comprised of five to eight Muslim Brothers, and they execute the Guidance Office’s orders at the local level throughout Egypt. Such directives can include everything from managing social services to mobilizing the masses for pro-Brotherhood demonstrations, to supporting Brotherhood candidates during elections.
The union of a committed membership and a clear chain-of-command provides the Muslim Brotherhood with a well-oiled political machine and thereby a tremendous advantage over the Salafists. Indeed, whereas the Brotherhood is one cohesive entity that can summon hundreds of thousands of veritable foot soldiers, not to mention the millions of ordinary Egyptians who benefit from its social services, to execute its agenda, the Salafist movement is entirely decentralized and spread out among a plethora of Salafist groups, schools, and shaykhs.
In a certain sense, Salafists are mirror images of Muslim Brothers in that they privilege ideological objectives above organizational ones. Indeed, many Salafists are “quietist,” in that they view Salafism as a personal religious commitment and reject attempts to politicize it: “I don’t have to join any organization to be more religious,” stated Bakr, a Salafist who participated in the youth coalition that organized the 2011 anti-Mubarak protests, when asked why he never considered joining the Muslim Brotherhood, he said: “There is no organization in Salafism because an organization needs a target. And there is no target in Salafism, the only point is dawa (outreach).” Even those Salafists who are deeply involved in Salafist organizations view their affiliation as secondary to their personal religious commitments. “Salafist streams are movements and different schools, not an organization,” said al-Gamaa al-Islamiya member Abdullah Abdel Rahman, son of the infamous “Blind Shaykh” Omar Abdel Rahman, who was convicted for his involvement in the 1993 World Trade Center bombing. “It’s a way of life. Anyone who follows the Holy Book and Sunna, they call him a Salafist. They don’t have a certain person to follow. … They all have their own schools, but agree on one way.”
Salafism’s deeply personal, self-directed nature is perhaps most evident in the independent process through which one becomes a Salafist. In stark contrast to the Muslim Brotherhood’s five-to-eight-year, four-stage process of internal promotion, one becomes a Salafist simply by declaring himself a “multazim,” or “obligated” to follow a literalist interpretation of the Qur’an and Sunna. Typically, a multazim attaches himself to a specific Salafist shaykh, with whom he studies how to live a deeply conservative lifestyle. But the multazim can choose his shaykh, unlike a Muslim Brother, who is assigned to an usra and handed a standardized curriculum.
It is a long article, written after the passage of the Islamist dominated constitution in 2012, but still relevant.
It is too early to say how things have changed, but I imagine Muslim Brotherhood recruitment is rather difficult now. Much of their upper leadership is in prison, but presumably the lower ranks can carry on activity, however impeded. I gather their usras explain much mobilizing force behind recent smaller area protests.
As for Salafis, the question is if the leading sheikhs have been compromised by cooperation with the current government. It may be much easier, however, for the average Salafi-inclined individual to resort back to a quietist, non-political faith that had long accepted the misguided rule of Mubarak, which if less than legitimate made rebellion also illegitimate for the social strife it would incur.
But the present is still being written, so we will see.