You most definately can attend our services at any time, though that doesn't make you a Latter-day Saint or Mormon.  
 
To become a member of the Church of Jesus Christ of Latter-day Saints you will go through 4 missionary lessons that will talk about the core doctrine of the Church.  
 
The Message of the Restoration of the Gospel of Jesus Christ, The Plan of Salvation, The Gospel of Jesus Christ, and the Commandments are the lessons you will be taught by the missionaries.  
 
After you have been taught those lessons and have attended Church at least 3 times, you are and eligible candidate for baptism.  
 
To be baptized you will have a Baptismal Interview from a missionary or the Mission President. This interview is not between you and the interviewer but between you and Heavenly Father, with the missionary/Mission President acting on behalf of Heavenly Father to ask you the questions.  
 
Here are the Questions that are asked: 
 
1.Do you believe that God is our Eternal Father? Do you believe that Jesus Christ is the Son of God, the Savior and Redeemer of the world? 
 
2.Do you believe the Church and gospel of Jesus Christ have been restored through the Prophet Joseph Smith? Do you believe that Thomas S. Monson is a prophet of God? What does this mean to you? 
 
3. What does it mean to you to repent? Do you feel that you have repented of your past transgressions? 
 
4. Have you ever committed a serious crime? If so, are you now on probation or parole? Have you ever participated in an abortion? a homosexual relationship? 
 
5. You have been taught that membership in The Church of Jesus Christ of Latter-day Saints includes living gospel standards. What do you understand of the following standards? Are you willing to obey them?  
 
a. The law of chastity, which prohibits any sexual relationship outside the bonds of a legal marriage between a man and a woman? 
 
b. The law of tithing. 
 
c. The Word of Wisdom. 
 
d. The Sabbath day, including partaking of the sacrament weekly and rendering service to fellow members. 
 
6. When you are baptized, you covenant with God that you are willing to take upon yourself the name of Christ and keep His commandments throughout your life. Are you ready to make this covenant and strive to be faithful to it? 
 
Once the interview is complete and you are approved for baptism, you are ready to be Baptized and confirmed a Member of the Church. Once you are confirmed a member of the Church you are a Mormon.  
 
You also then can receive various callings, be ordained to the priesthood (for boys and men age 12+), and start your preparation to go to the Temple for various ordinances that are done in the Holy Temple!