For me it took only a few days before the next one, however I had been remembering dreams for about a year or so before I found out about lucid dreams, which may have helped me in some ways. Despite having them quite fast, it actually took a while before I had one that was very vivid and stable. About 2 months or so. My first technique were of using WILD, as I seemed to naturally wake during the night. I eventually started having DILD's and found that they were more stable and vivid for me so I tend to rely mostly on that.

Hope this helps in some way, and wish you all the best with your lucid journey =)

It should eventually become easier and easier...