Once in a lobby or match, type !dr 50 (or your chosen value) into the chat to apply the change.
This tool is primarily designed for "Classic" versions (patch 1.26 to 1.28). Users on Warcraft III: Reforged should instead look into built-in Gameplay Options like "Reduce Mouse Lag" or official patch updates that have improved native FPS and responsiveness.
In modern versions of the game, many host bots have built-in delay reducers, making external tools less necessary for players who aren't hosting.
Use in-game chat commands like !dr to set your preferred delay in milliseconds.