What type of partner should you introduce?
Ideally you should not think about introducing a new partner until your children have become used to the fact that you are single. They will need time to adjust and accept that your relationship with the other parent is over, and that there is no chance of reconciliation. Introducing a new partner before there has been time to process the separation can be very disruptive to children who are already quite confused.
It is possible that you will date a number of people before finding a serious relationship. Try not to introduce your kids to what might be a short-term partner; it will only confuse and frustrate them. Then, when the time comes that you do want them to meet someone with whom you are developing a serious relationship, it will take them longer to trust that person.
It is best to wait until you have a committed relationship with someone before introducing your children into the equation. Give things time to reach stability, where you and your new partner are comfortable with each other. Wait until the “honeymoon phase” is over, or at least less intense. Feel free to talk to your new partner about your children beforehand, but go slowly with the introductions.