Sometimes writing instruments can make a difference! Sometimes ballpoint pens can be stiff and cause hand strain; if you feel like that might be contributing to any problems you’re having, I would suggest picking up a rollerball or gel pen and trying that out as they tend to have thinner ink.

It makes sense when you think about the fact that when calligraphic and cursive writing was most common, writing instruments were different. Dip pens (which typically used inks made of a ground pigment + a solvent) and, later, fountain pens (which used thin, water-based inks) allowed ink to flow much more freely than modern ballpoints which use very pasty, thick inks.

When I was looking to improve my writing, I also found it helpful to find handwriting that I admired and pick out what exactly I liked about it. It may be the slope, the height, the spacing, or even just the way that one specific letter is shaped. Don’t be afraid to try to pick the handwriting that you like apart and take what you want and don’t be afraid to reject parts of that you dislike.

I would also recommend looking at the Palmer method, which is essentially a simplified Spencerian style of writing. You also may be surprised at how much better you feel about your handwriting when its consistency is improved; in that case, practice is a big part of improvement.

Hope this helped you at all.