Hi
surely youve changed your rubber in 3 months
put your rubber through your channel, put the brass clip on the end of your rubber leaving the smallest bit of rubber then push the clip in, that will secure one end. The other end pull your rubber through and put the brass clip on and push in leaving a small bit of rubber showing.
Alternatively just get yourself an Unger ergotech squeegy they are quick release rubbers and you do not need end clips
regards
Brett.