What are the best tools to use to make wood look aged?

https://www.pinterest.com/explore/aged-wood/?lp=true

A screwdriver and the side of a file...

Sand paper and vinegar ages the wood

chain and hammer.....all good suggestions. There are so many "aged" looks. Choose the one you like and then google how to best get that technique

I do a lot with reclaimed wood that has it's own look. BUT I still must deal with fresh cuts. (cross cuts that exposes end grain and rip cuts that exposes straight grain). I often take the project outside and burn the newley exposed wood with a propane/butane torch. It is not uncommon for me to burn the daylights out of it. After you change the texture you can wire brush (wire wheel in a drill) the soot/char away and to achieve the look you want. You probably can't get rid of all the cha/dark color. If you are painting it is of no concern. If you are going to leave it natural, then I would recommend staining the piece as dark as your taste allows - BUT be sure to seal the end grain with shellac before stain because it will get really dark. I believe you could distress completely new lumber with this technique. Just be sure you practice on some scrap first. I will try to reply with a photo if I can find one, otherwise I will post a tutorial next time I use this technique. Good luck..

I found a photo of an industrial cart I made years ago. The sides are made from various pieces of wood and molding I had on hand. The fresh cut ends were blended with my torch technique. Stained way too dark for current tastes. If I were to do it today I would have sanded/plane the top boards to keep them light. Hope this make sense.