Islam is fully complete

It is known by necessity that the Deen of Islam is complete, as Allah, the Exalted, says:

...This day have I perfected your religion for you, completed my favour upon you, and have chosen for you Islam as your religion.... (Quran 5 : 3)

Shari'ah is fully complete. So follow Islam only.

Interprets - Express Your Own Ideas

It is not fitting for a Believer, man or woman, when a matter has been decided by Allah and His Messenger, to have any option about their decision: if anyone disobeys Allah and His Messenger he is indeed on a clearly wrong Path. (Qur’an 33 : 36)

Narrated Jundub: The Prophet (peace_be_upon_him) said: If anyone interprets the Book of Allah in the light of his opinion even if he is right, he has erred. (Sunan Abu Dawud Book 25, Number 3644:)

Innovations (Bid’ah)

Every Religious Innovation is a Means of Misguidance

Prophet Muhammad (Peace Be Upon Him) said: "Every newly-invented thing is a bid'ah (innovation), every bid'ah is a going astray, & every going astray will be in the Fire." ( Al-Nisaa'i in al-Sunan )

Beware of excessiveness in Religion . (i . e . extremism or exceeding the bounds) (Nisayee . sahih)

"Leave That Which Makes You Doubt For That Which Does Not Make You Doubt" . (Tirmizi)

Islam is simple, don’t make it complicated

Narrated Abu Huraira: The Prophet (ﷺ) said, "Religion is very easy and whoever overburdens himself in his religion will not be able to continue in that way. So you should not be extremists, but try to be near to perfection and receive the good tidings that you will be rewarded; and gain strength by worshipping in the mornings, the afternoons, and during the last hours of the nights." (See Fath-ul-Bari, Page 102, Vol 1)

(Sahih al-Bukhari - Vol. 1, Book 2, Hadith 39)

Follow Qur’an And Sunnah To Save Our Imaan

Yahya related to me from Malik that he heard that the Messenger of Allah, may Allah bless him and grant him peace, said, "I have left two matters with you. As long as you hold to them, you will not go the wrong way. They are the Book of Allah and the Sunna of His Prophet." (Malik muwatta Book 46, Number 46.1.3)

The most miserable loser is a man who knows the path to Allah yet he turns away from it.