It is preferable to wash one’s hands and then get dressed, in order to remove the ruach hatumah sooner. However, clothing that are necessary to wear in order to go wash may be put on beforehand. Therefore to put on one’s eyeglasses is permitted.
When washing, one should try to remove all possible separations (chatzitza) between their hands and the water.
If after one washed their hands they touched another person’s hands who did not wash yet, they do not need to wash again. However, the Ben Ish Chai writes that one should wash again. One may rely on the lenient opinion, but when possible, should wash again.