You would have to do a stipulation and order. The paperwork would have to be submitted to the court. The court may or may not approve it. Even with a lawyer, the court does not always approve a terimation of parental rights especially if there isn't a step-parent adoption and a reason for terminating the rights.
I would suggest that you spend a little money for a competent attorney.
Some of this answer might be redundant from the last, but hopefully it will provide you with some more insight into the process. Prior to the stipulation you will likely want to file a petition to terminate parental rights.
A Petition to Terminate Parental Rights is a petition to the family court asking the court to take away the rights of a parent by court order. There are a number of reasons to seek a termination of parental rights ranging from protecting the interests of a child to preparing for the adoption of a child.
It is always important to seek competent legal counsel before filing a Petition to Terminate Parental Rights. Nevada law requires very specific information to be plead in a Petition before the court will even consider it.
While the Nevada statutes (N.R.S. 128) enumerate at length the possible reasons for termination of parental rights, the court focuses their decision on the best interests of the child as well as the conduct of the parent toward the child.
These considerations generally include:
The Child's wishes;
Abandonment of the child;
Neglect of the child;
Unfitness of the parent;
Failure of parental adjustment;
Risk of serious physical, mental or emotional injury to the child if he were returned to, or remains in, the home of his parent or parents;
Only token efforts by the parent or parents (a) to support or communicate with the child, (b) to prevent neglect of the child, (c) to avoid being an unfit parent, (d) to eliminate the risk of serious physical, mental or emotional injury to the child, or (g) with respect to termination of the parental rights of one parent, the abandonment by that parent.
Pleading to satisfy these considerations must be done with care. When considering these factors, the court's final decision will not only rely upon the plain language of Nevada statutes, but also decades of complex and seemingly contradictory decisions from previous Nevada cases.
If the court finds the pleadings insufficient then they might deny your petition or any stipulation to terminate parental rights.
Again, if you do go down this path, it is critical that you contact competent counsel to help you through the process.