Yes, this is effective and easily to follow, even print it out and carry it with you. Give it to those you witness to. You should put your name at the bottom and the phone number of the church you attend or any other personal ministry affiliation you have.
Memorizing all of the gospel verses may be too hard to begin with. If so, memorize the six verses and become proficient in the Short Gospel Presentation as cited below. Once you master it, memorize the rest as presented here:
Memorize Matthew 25:46; Mark 8:36-37; John 1:12; 3: 1-7, 16, 36; 14:6; Acts 4:12; Romans 3:23; 5:8; 6:23; 9:9-10; 10:13; 2 Corinthians 6:2b; Hebrews 9:27; Revelation 20:15, and learn how to share the gospel. At times you might forget to take your spiritual sword (Bible) or dagger (New Testament) with you. If you have the key salvation passages memorized you can quote them.
Short Gospel Presentation
Everyone is a sinner in need of salvation:
“For all have sinned, and fall short of the glory of God” (Romans 3:23).
Those who die in their sins will be judged:
“And inasmuch as it is appointed for men once to die, and after this comes judgment” (Hebrews 9:27).
Yet even though all have sinned, one can escape eternal punishment in the Lake of Fire, and have eternal life through Jesus Christ:
“For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord” (Romans 6:23).
Salvation is available to all is a sinner in need of salvation:
“For all have sinned, and fall short of the glory of God” (Romans 3:23).
Those who die in their sins will be judged:
“And inasmuch as it is appointed for men once to die, and after this comes judgment” (Hebrews 9:27).
“But God demonstrates His own love toward us, in that while we were yet sinners, Christ died for us” (Romans 5:8).
Belief in Jesus Christ apart from works is the only way to be saved:
Jesus said to him, “I am the way, and the truth, and the life; no one comes to the Father but through Me” (John 14:6).
“For by grace you have been saved through faith; and that not of yourselves, it is the gift of God; not as a result of works, so that no one may boast” (Ephesians 2:8-9).
If you believe God the Father raised Jesus from the dead, call upon Jesus Christ to save you right now:
For “WHOEVER WILL CALL ON THE NAME OF THE LORD WILL BE SAVED” (Romans 10:13).