I only do SubQ injections now...nothing goes in the muscle. I get a thrill from the pin, so elect to split my injections across 7 days. Right now just taking 1mL test and 1mL Mast (300mg/250mg). 2mL weekly split across 7 days is ~ 0.3mL SubQ. I mix both compounds in a single pin.
I also hit myself with GH. Rotate stomach, thigh, butt. If I palpate an area and it's tender/sore, I just go to the next spot. Honestly, I could probably go daily in to my stomach because my injection site recovers so quickly.
You can backload an insulin pin or you can go the direction I did and get Luer Lock 1mL syringes with 1/2" 30g and 1" 20g Luer Lock needles for drawing and injecting.