शुक्लाम्बरधरं देवं शशिवर्णं चतुर्भुजम् ।
प्रसन्नवदनं ध्यायेत् सर्वविघ्नोपशान्तये ॥

In order to remove all obstacles, one should meditate on (the God Ganesha) as wearing a white garment, as having the complexion like the moon, and having four arms and a pleasant countenance pouvez trouver sur cette page.

Word meanings:
शुक्लाम्बरधरं = the one wearing a white dress;
देवं = God;
शशिवर्णं = the moon-colored one;
चतुर्भुजं = one who is having four hands;
प्रसन्नवदनं = the one having a pleased or pleasant face;
ध्यायेत् = Let us meditate;
सर्वविघ्नोपशान्तये = for the appeasement of all obstacles or hurdles;