stitch in the ditch is a very hard method for anyone, especially for a beginner. use a matching thread for that with a very busy fabric for the backing for 'forgiveness'.
when you stipple or meander, move your whole upper body. i think you'll find it easier if you loosen up and try not to get too tense.
for practicing, do lots of loops, in all directions. then do wiggles. don't only do meandering. get used to the feeling of moving in all ways. spell out your name. follow drawn lines. you don't have to start out being creative. that will come. right now you want to be smooth. don't get nervous. keep practicing and when you feel that you're tightening up, stop and relax for a while. have a glass of wine. spell out the name of the wine. have fun with it. the bulb will light up over your head and you'll have it!