• Sunnat-ul-Qual: all words, counsels or precepts of the Holy Prophet (PBUH)
• Sunnat-ul-Fieel: his action, works and daily practices
• Sunnat-ul-Taqrir: his silence implying a tacit approbation on his part of any individual act committed by his disciples

Can a Muslim of one sect change to another Sect?
A Muhammadan male of female who has attained the age of puberty, may renounce the doctrines of the sect or sub-sect to which he or she belongs and adopt the tenets of the other sects or any other sub-sect, and he or she will thenceforth be subject to the law of the new sect of subs-sect.
It is important to be a Muslim and there is not restriction on changing of sect in Islam. One must fulfill the original requirements to be a Muslim while remaining in any sect. There are some sects which not fulfill the requirement of Muslim and conversion to such sect made one apostle hence the essential point in this question to retain the basic requirements of Muslim.
In your previous article we have discussed the Definition of Muslim, you can read it by clicking on the given link.

Narrated `Aisha: Whenever the Prophet took a bath after Janaba he started by washing his hands and then performed ablution like that for the prayer. After that he would put his fingers in water and move the roots of his hair with them, and then pour three handfuls of water over his head and then pour water all over his body.
1.249:
Narrated Maimuna: (the wife of the Prophet) Allah’s Apostle performed ablution like that for the prayer but did not wash his feet. He washed off the discharge from his private parts and then poured water over his body. He withdrew his feet from that place (the place where he took the bath) and then washed them. And that was his way of taking the bath of Janaba.
1.250:
Narrated `Aisha:
The Prophet and I used to take a bath from a single pot called ‘Faraq’.
1.251:
Narrated Abu Salama: `Aisha’s brother and I went to `Aisha and he asked her about the bath of the Prophet. She brought a pot containing about a Sa` of water and took a bath and poured it over her head and at what time there was a screen between her and us.
1.252:
Narrated Abu Ja`far: While I and my father were with Jabir bin `Abdullah, some People asked him about taking a bath He replied, “A Sa` of water is sufficient for you.” A man said, “A Sa` is not sufficient for me.” Jabir said, “A Sa was sufficient for one who had more hair than you and was better than you (meaning the Prophet).” And then Jabir (put on) his garment and led the prayer.
1.253:
Narrated Ibn `Abbas: The Prophet and Maimuna used to take a bath from a single pot.
1.254:
Narrated Jubair bin Mut`im: Allah’s Apostle said, “As for me, I pour water three times on my head.” And he pointed with both his hands.
1.255:
Narrated Jabir bin `Abdullah: The Prophet used to pour water three times on his head.
1.256:
Narrated Abu Ja`far: Jabir bin `Abdullah said to me, “Your cousin (Hasan bin Muhammad bin Al−Hanafiya) came to me and asked about the bath of Janaba. I replied, ‘The Prophet uses to take three handfuls of water, pour them on his head and then pour more water over his body.’ Al−Hasan said to me, ‘I am a hairy man.’ I replied, ‘The Prophet had more hair than you’. ”
1.257:
Narrated Maimuna: I placed water for the bath of the Prophet. He washed his hands twice or thrice and then poured water on his left hand and washed his private parts. He rubbed his hands over the earth (and cleaned them), rinsed his mouth, washed his nose by putting water in it and blowing it out, washed his face and both forearms and then poured water over his body. Then he withdrew from that place and washed his feet.

Narrated Maimuna:
I placed water for the bath of Allah’s Apostle and he poured water over his hands and washed them twice or thrice; then he poured water with his right hand over his left and washed his private parts (with his left hand). He rubbed his hand over the earth and rinsed his mouth and washed his nose by putting water in it and blowing it out. After that he washed his face, both fore arms and head thrice and then poured water over his body. He withdrew from that place and washed his feet.
1.266:
Narrated Maimuna bint Al−Harith: I placed water for the bath of Allah’s Apostle and put a screen. He poured water over his hands, and washed them once or twice. (The sub−narrator added that he did not remember if she had said thrice or not). Then he poured water with his right hand over his left one and washed his private parts. He rubbed his hand over the earth or the wall and washed it. He rinsed his mouth and washed his nose by putting water in it and blowing it out. He washed his face, forearms and head. He poured water over his body and then withdrew from that place and washed his feet. I presented him a piece of cloth (towel) and he pointed with his hand (that he does not want it) and did not take it.
1.267:
Narrated Muhammad bin Al−Muntathir: on the authority of his father that he had asked `Aisha (about the Hadith of Ibn `Umar). She said, “May Allah be Merciful to Abu `Abdur−Rahman. I used to put scent on Allah’s Apostle and he used to go round his wives, and in the morning he assumed the Ihram, and the fragrance of scent was still coming out from his body.”