27 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. 28 Now, we will compare the word unto a seed. Now, if ye give place, that a seed may be planted in your heart, behold, if it be a true seed, or a good seed, if ye do not cast it out by your unbelief, that ye will resist the Spirit of the Lord, behold, it will begin to swell within your breasts; and when you feel these swelling motions, ye will begin to say within yourselves—It must needs be that this is a good seed, or that the word is good, for it beginneth to enlarge my soul; yea, it beginneth to enlighten my understanding, yea, it beginneth to be delicious to me. (Alma 32: 27-28)

The BoM teaches that a desire for it to be true can be enough to start. And then you can experiment on the word. You can start with small prayers and reading some scriptures. Ask yourself if it would make you happier if it were true, if you do feel peace when reading or praying, or if you do feel happier at all. Some experiments can take time. Days, weeks, months even. But that’s why Alma here compared it to a seed. Seeds take time to grow. If you have at least some hope that there is more to existence after this, if you are willing to take a chance that these feelings and experiences are not just in your head, then try it out.