The Letter Mem is another letter which has a special letter which replaces it when it is used at the end of a word. The Mem is made up of two different letters- a Chof Peshuta, and a Vov. The dimensions of the Mem are 3X3 kulmusim. That is, that the top and bottom of the Chof Peshuta part of the Mem , are only 2 kulmusim in length. The top right corner should be rounded, (like a Letter Chof Peshuta should be,)and the right leg would then go down until it reaches a total length of 3 kulmusim. By the same token, the space in middle of the Mem Pesucha should equal 1 kulmus. The bottom right corner of the Mem should be squared. The Vov part of the Mem, (which is sometimes referred to as the "nose") should be angled so that the face of the Vov is angled upward. At the point where the head of the Vov connects to its leg, is where the Vov should touch the Chof Peshuta part of the Mem . There should be a clear notch in between the two heads of the letters. Also, the connection between them should be thick, so that it's clear they are connected. At the bottom, the Vov and Chof Peshuta must not touch at all, as that would invalidate the letter since it would become a Mem Stumah.