Because it is so close to the sun, Mercury always appears low on the horizon where the atmosphere is thick and unstable. This causes Mercury to take on a yellowish color and makes telescopic observation tough.

For the best view, try to observe Mercury an hour before sunrise in the morning sky. The atmosphere is most stable at sunrise, since the sun has not yet had a chance to heat up the ground and produce rising air currents.

You won't be able to see any surface features, even with a very large amateur telescope. But with a magnification of at least 50X you should be able to see Mercury's phases. The planet changes from gibbous to crescent phase in less than three weeks.