The layout of the songs, and other issues
1. One leaves an entire blank line before Shirat ha-Yam, which itself is written on thirty lines. The first line is written normally, and for the rest of the lines, one is broken into three parts with two gaps, the two gaps together making the length of a setuma break, and the next has a setuma-sized break in the middle. This gap is lined up with the writing, and the writing is lined up with the gap. An entire blank line is also left at the end of it. The custom is to write five lines at the top of the page on which Shirat ha-Yam is to be written, the first line (at the top of the page) starting “Ha-baim,” the second “va-yabasha,” the third the Tetragrammaton, the fourth “met,” and the fifth “be-mitzrayim.” So too are there five lines after it, starting: “va-tikaḥ,” “aḥarehah,” “sus,” “va-yetzu,” and “va-yavou.” This is the ideal way, but its omission does not invalidate.
2. Shirat Ha-azinu also has a blank line left before and after it, and one writes it on seventy lines, each line divided into two by a setuma break. It is the custom to write six lines at the top of the column before the Song, starting “ve-a-ida,” “aḥarei,” “ha-derekh,” “be-aḥarit,” “l-hakh-iso,” and “kahal;” and to conclude it with the five lines starting “va-yavo,” “l-daber,” “asher,” “ha-zot,” and “asher.” This too is the ideal way and its omission does not invalidate.
3. If one wrote the Song like the ordinary writing, or ordinary writing like the Song, it is invalid. This is if he wrote it just like any other writing, without its being broken up into pieces. If he changed the precise way it is broken up, it is not invalid, provided that Shirat ha-Yam has text blocks over blank spaces and Shirat Ha-azinu has text blocks lined up one on top of the other.
4. There are various traditions which are passed from scribe to scribe concerning the large and small letters, and the dots, and the altered letters. Ideally one does these, but their omission does not invalidate. One should take care that the dots do not resemble yuds or any other letter forms (responsa of R’ Menaḥem Azariyah, #38).
5. Some scribes are careful always to start columns with one of the letters ב, י, ה, ש, מ, ו. That is, ב from Bereshit; י from Yehudah ata (Gen. 49:8); ה from Ha-baim aḥareihem (Ex. 14:28); ש from Shmar lekha (Ex. 34:11) – some say from Shnei ha-se-irim goralot (Vay. 16:8) and some say from Shmor ve-shama-ta (Deut. 11:28); מ from Ma tovu (Num. 24:5), and some say from Motza sfateikha (Deut. 23:24); and ו from Ve-a-idah bam (Deut. 32:28). Post facto, if one didn’t write it this way, it isn’t invalid. Some have the custom to start each column with a vav – calling it vavei he-amudim – and this should be discouraged, because the letters are so squashed and stretched to achieve it that it comes to be written incorrectly, and spoiled. Even if one can do it without unduly squashing and stretching the letters, he should still refrain, because other people will think that they can do it too, even if they can’t space their writing properly, and they will squash and stretch letters just as they please (Benei Yonah).
6. A sefer Torah with nikud (vowels) is invalid. This is because we have a received tradition for the letters, and once one adds vowels, it is only a reading tool [the received tradition for the vowels is much less old]. It is still invalid even if the vowels are removed, because they show that the scribe was intending for it to be a reading tool and not a rendition of the letter tradition, so it lacks authenticity (Taz). However, if the sefer Torah was written correctly and someone added vowels or musical notation afterwards, they may be erased just like other mistakes (B.L.I. and Noda be-Yehuda tenina sec. 172). A sefer Torah which has the verse divisions marked in ink is also invalid; some say that it can be remedied by scraping even if it was written that way originally, and some say it can’t (Benei Yonah).
7. One shouldn’t leave a bigger gap between verses than he would between words, even if there is nothing written in it. However, post facto it is valid, provided the gap is not so large as to be a paragraph break. Some do leave a small gap on purpose, and that is all right because they have support (Benei Yonah) – but in any case the gap should not be as large as two letters (because this is a paragraph break according to Rabeinu Tam, see the Beit Yosef in 275) (Melekhet ha-Shamayim).