First thing Ты gotta do, is find an old gardening, sports, или construction tool that no one uses anymore, e.g., a shovel, baseball bat, lead pipe, etc.
Then Ты gotta make it look еще shitty than it already is by wrapping tape and или strings around it.
After that, Ты gotta put some DIY mods on it to make it do еще damage. For example, Ты can put some spikes on your bat или put a bunch of rocks in an old pipe to make it heavier.
Once no one suspects the weapon of choice, Ты can take out your target, but do it this exact way: Follow them, tap them on the shoulder, then when they look back, knock them out by hitting them as hard as Ты can with your fist and или the club.