When I started to dance, I preferred improvisation to choreography. I found choreography hard to remember and limited in the variations of movements. Remembering choreography was my biggest challenge during my early years of performances. I would get really stressed out about it before performances. Improvisation takes some of that pre-performance anxiety away from me. Since each song I danced to had a different feeling, I tended to move in a certain way every time I improvised. For every improvisation experience, I made up new movements to add to my repertoire. But as I had discovered, being a good improviser takes a lot of work.
One of the biggest challenges for me is to synchronize with the music. Improvisation looks really good if the movements respond to the music, but it was hard for me to achieve that. Feeling comfortable and confident on stage was the solution I found in order for me to only focus on the music and my movements rather than being distracted by other things. It also helped to choose the music that I resonated with. Things became easier when I understood the music. This way I could break the songs into sections to mark the transitions of the mood, giving a twist to the quality of movements. Another challenge for me is making my movements more concise. I had the tendency to be constantly moving, but sometimes the dance would look better if I had slowed down and gotten into a pose. The way to solve this problem was to get my muscles constantly used in the dance stronger. It takes less energy for muscles to do the exact dances that it had done for many times as opposed to thinking about what to do on the spot. That is why a good dance improvisation is very physically demanding. A way that I can feel more secure about my improvisation is to remember a few movements that I found worked well in my practice, so that I can always go to those movements when I did not know what to do. It was also important to think about how I wanted to start and end the dance.
There are various workshops which dancers can attend to become better improvisational dancers. I definitely suggest that dancers go to those, because being in a class with confined time and space give a different feeling than working alone. A lot of the workshops that I attended to taught me the awareness of the space that I am in and the organic movements of my body. To be a good improviser, one has to find his or her authentic ways to move and have imaginations of shapes in the brain. Some may find themselves going through and feeling the movements, while others hit on the beats.
Here is a useful website that I found which talks about how to improvise a dance.