Gaining a testimony of anything requires faith. You may feel like you don't have sufficient faith, or maybe you feel like you don't have any faith at all. To those people who are struggling to gain a testimony of the Gospel of Jesus Christ, listen to the words Alma, a prophet from the Book of Mormon, teaches:
"And now as I said concerning faith--faith is not to have a perfect knowledge of things; therefore if ye have faith ye hope for things which are not seen, which are true."
"But behold, if ye will awake and arouse your faculties, even to an experiment upon my words, and exercise a particle of faith, yea, even if ye can no more than desire to believe, let this desire work in you, even until ye believe in a manner that ye can give place for a portion of my words." (Alma 32:21,27)
As Alma said, faith is not to have a perfect knowledge of things. You may feel like the most cynical or disbelieving person, but I promise that if you will take Alma's promise to "experiment upon the word" and "exercise a particle of faith", you too can find the peace and happiness that only the Gospel of Jesus Christ brings. After all, Christ did not come to redeem just some of mankind--He came for you too.
"Faith is like a little seed, if planted it will grow"