Assuming you're using the default c-shell on the Ondemand cluster, open the resource file $HOME/.cshrc and append the following lines:

setenv cilkpath "/usr/local/apps/CILK"
set path = ( $path $cilkpath/bin )      

Exit and relogin. Type cilk++ and you should get:
>> cilk++: no input files

Try to run cilk's quicksort example (in your local directory) :

%  cp -r $cilkpath/examples/qsort /your_local_directory/qsort
%  cd /your_local_directory/qsort
%  make
% ./qsort

This should succeed.

For experimentation, use different number of workers:

% ./qsort -cilk_set_worker_count 1
% ./qsort -cilk_set_worker_count 2
% ./qsort -cilk_set_worker_count 3
% ./qsort -cilk_set_worker_count 4