I always keep a copy of the original schedule, including the original (agreed) baseline (and copies of subsequent client agreed changes).
Then I make a copy of the original (or current) baseline. Add the client changes to that version (untramelled by the reality of a 5 day slip). I usually add them at the end of the tasklisk under the heading Change Requests. In your current schedule:
Copy/move your current baseline to Baseline 1 (or Baseline n – depending on how many changes you client has asked for since you began).