The ornamental design for a warmingcap for a shoe or boot, substantially as shown and described.
FIG. 1 is a front right perspective view of a warming cap for a shoe or
boot showing our new design, the broken line disclosure being illustrative
of environment only;
FIG. 2 is a right side elevational view;
FIG. 3 is a front perspective view;
The bottom of the warming cap is substantially plain and unadorned.