Very cool Fenja!
Thank you so much! Is it easy to stretch out the custom shapes? I might have to upload them?
I'm not a native english speaker and so I have a problem with the meaning of "stretch out".
1. You want more shapes?
Google for "Photoshop custom shapes arrows" (be sure to get *.csh files!), some are for free, some aren't.
Unzip if necessary and store the *.csh here or anywhere on your HDD.
Load the shapes using the menu of the shapes panel.
2. You want to make an arrow longer/thicker?
Use for drawing the shape mode (not the pixel mode). This way the edges remain crisp.
3. You want to stretch the shapes panel?
Pull the bottom right corner of the panel.