Salvation is by faith alone in Jesus Christ as Lord (God) and Savior alone, in accordance with Scripture (the Bible) alone, by the grace of God alone, to God be all the glory. We cannot do anything to "help" "earn" Salvation and eternal life, and to say we can steals glory from Jesus, who did it all for us. Stealing glory from Jesus is a sin of vanity and denies the sufficiency of Jesus' work on the cross to pay for everyone's sins that have been committed or ever will be committed.
The only good works that count for anything are those done AFTER Salvation by faith in Jesus Christ, and they only count for rewards in Heaven, NOT toward Salvation. The only works that count toward the rewards in Heaven are those that aren't burned up when we arrive at the Bema seat of Christ. The good works referred to in Ephesians 2 are the good works God has prepared and equipped us to do for Him in His service AFTER we are saved, and our Salvation is NOT conditional upon them.
Catholics and Orthodox believe in works being necessary for Salvation, not just for rewards in Heaven. Some legalistic Protestants, while denying works-based Salvation, say people have to do good works as "evidence" of being saved or to "maintain" Salvation, but this is not true, as it is another form of works-based Salvation.
I heard part of a TV evangelist's message yesterday that was spot-on on this topic. Essentially, once we are saved, even when (not if) we sin or when (not if) we don't live up to what we're supposed to do, we won't lose our Salvation because that would be a works-based Salvation. God created us with free will and we don't lose free will when we're saved by faith in Jesus Christ, so even after we're saved, we still sin. However, since Jesus died for all of our sins that we ever committed or will ever commit, God now sees Jesus' righteousness, which is imputed to us at the moment of Salvation, instead of our sins and unworthiness (whew!)
8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
9 Not of works, lest any man should boast.
10 For we are his workmanship, created in Christ Jesus unto good works, which God hath before ordained that we should walk in them.
Ephesians 2:8-10, KJV
16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
17 For God sent not his Son into the world to condemn the world; but that the world through him might be saved.
18 He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God.
John 3:16-18, KJV
3 For what saith the scripture? Abraham believed God, and it was counted unto him for righteousness.
4 Now to him that worketh is the reward not reckoned of grace, but of debt.
5 But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness.
6 Even as David also describeth the blessedness of the man, unto whom God imputeth righteousness without works,
7 Saying, Blessed are they whose iniquities are forgiven, and whose sins are covered.
8 Blessed is the man to whom the Lord will not impute sin.
20 He staggered not at the promise of God through unbelief; but was strong in faith, giving glory to God;
21 And being fully persuaded that, what he had promised, he was able also to perform.
22 And therefore it was imputed to him for righteousness.
23 Now it was not written for his sake alone, that it was imputed to him;
24 But for us also, to whom it shall be imputed, if we believe on him that raised up Jesus our Lord from the dead;
25 Who was delivered for our offences, and was raised again for our justification.
Romans 4:3-8, 20-25, KJV
1 Blessed is he whose transgression is forgiven, whose sin is covered.
2 Blessed is the man unto whom the Lord imputeth not iniquity, and in whose spirit there is no guile.
5 I acknowledge my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the Lord; and thou forgavest the iniquity of my sin. Selah.
Psalm 32:1-2, 5, KJV
