The most common tool in this toolbox is "time-outs". My wife and I just didn't feel comfortable with this - it felt humiliating and mean - and the research seems to be confirming it's not the best approach
The studies found that both positive and negative conditional parenting were harmful, but in slightly different ways. The positive kind sometimes succeeded in getting children to work harder on academic tasks, but at the cost of unhealthy feelings of “internal compulsion.” Negative conditional parenting didn’t even work in the short run; it just increased the teenagers’ negative feelings about their parents.
What these and other studies tell us, if we’re able to hear the news, is that praising children for doing something right isn’t a meaningful alternative to pulling back or punishing when they do something wrong. Both are examples of conditional parenting, and both are counterproductive.
In practice, according to an impressive collection of data by Dr. Deci and others, unconditional acceptance by parents as well as teachers should be accompanied by “autonomy support”: explaining reasons for requests, maximizing opportunities for the child to participate in making decisions, being encouraging without manipulating, and actively imagining how things look from the child’s point of view.
The last of these features is important with respect to unconditional parenting itself. Most of us would protest that of course we love our children without any strings attached. But what counts is how things look from the perspective of the children — whether they feel just as loved when they mess up or fall short