Pre-registering experiments is a good practice to avoid multiple potential biases when interpreting results post-hoc, and improving reproducibility. It basically consists of pre-documenting what the experiment looks like, what data is to be collected and how, what analyses will be ran on the collected data, and what are the expected results. This is especially important in experimental psychology, where human experiments have historically been notoriously hard to reliably reproduce.
The Open Science Foundation has a platform for doing pre-registration. You can then link to the pre-registration in your paper.