My advice would be to keep writing in your dream journal, then read over your dream journal and try to spot anything reoccuring (Dream sign) then reality check to this and anything that relates to this.

Also, as you're falling asleep think to yourself that you will remember all the dreams you have. Or "I am going to lucid dream tonight" something like that, and believe it.

Also, try to increase the number of crunches and push ups you do every day. It may not be beneficial to dreaming but it's always a good idea!