The Collaborative International Dictionary
To outdo oneself
Outdo \Out*do"\ (out*d[=oo]"), v. t. [imp. Outdid (out*d[i^]d"); p. p. Outdone (out*d[u^]n"); p. pr. & vb. n. Outdoing.] To go beyond in performance; to excel; to surpass.
An imposture outdoes the original.
--L' Estrange.
I grieve to be outdone by Gay.
--Swift.
To outdo oneself to surpass one's own previous best performance.