We are up to Mishnah 9 in the third chapter of Maseches Yoma. In the previous Mishnah we learned about the Kohen Gadol's first confession over the bull, and now he moves on to drawing the lots over the two goats: to determine which of them will be brought as a chatas offering, its blood sprinkled in the Holy of Holies, and which of them will be sent to Azazel.
The Kohen Gadol's Position and Those Standing Beside Him:
Until now the Kohen Gadol had been standing in the western part of the Azarah, and now - "ba lo l'mizrach ha'azarah litzfon hamizbe'ach" - he moves to its eastern part, to the northern side of the Altar. There, two men stand with him: "hasegan mimino v'rosh beis av mismolo".
The Segan - the deputy who stands ready to take the Kohen Gadol's place, and his position is at his right.
The Rosh Beis Av - a "beis av" is the group of kohanim assigned to serve on that particular day of the week that happened to fall out on Yom Kippur, and the head of that group stands at his left.
The Box and the Lots:
The two goats stood there, "v'kalpi haysah sham u'vah shnei goralos" - the kalpi is a box, and inside it the two lots were placed.
"shel eshkaro'a hayu, va'asa'an ben Gamla shel zahav" - originally the lots were made of a wood called eshkaro'a, and a Kohen Gadol named ben Gamla came and overlaid them with gold. Regarding this act - transforming the plain wooden lots into lots of gold - the Mishnah says "v'hayu mazkirin oso l'shevach", that the Sages took note of him and remembered him favorably.
In summary: In this Mishnah we learned that after the confession over the bull the Kohen Gadol moves to the east of the Azarah, to the north of the Altar, with the Segan at his right and the Rosh Beis Av at his left; there stand the two goats and the box containing the two lots, which were originally made of eshkaro'a wood until ben Gamla made them of gold - and for this he was remembered favorably.