If your little one is still attached to the shell, put a little dot of antibiotic cream on the drying out spots. Vaseline will work to keep it moist, but not to fight infection.
And even if this one doesn't make it, don't give up on hatching. These things happen to even the most experienced "chickeneers." The joy and wonder when it all goes well is worth the false starts ... and it all counts towards experience!
True true. Anybody who hatches runs into these types of chicks every year.