The principle is simple: you will see two curves of different colors on the screen, representing two polynomials. One is given by the server site, the other constructed by you. Your goal is to modify the coefficients of your polynomial, to make its curve coincide with that of the computer.
If after your first try, the two curves seem to be far too different, don't be discouraged; this is normal, and you have the right to several tries. The important thing is to find the good coefficients at the end.
Please take note that WIMS pages are interactively generated; they are not ordinary HTML files. They must be used interactively ONLINE. It is useless for you to gather them through a robot program.