Here´s my translation

Alan

Ok látum þá nú búast, en víkjum sögunni aftr til þeira kumpána, at þeir sigla, 
And (we, let’s) leave them (þá, ie the King et al) now to ready-themselves, but (and) (we, let’s) move the-story back to those companions, (such) that they sail.

þangat til at vegir skiljast ok annarr lá til Bjarmalands. 
till-that-point (in the space-time continuum) that (the) ways (sea routes) divide and one-of-the-two (ways) went (ie led, liggja, Z5) to Bjarmaland.

Þá bað Bósi Herrauð sigla heim til Gautlands, en hann kvaðst eiga erendi til Bjarmalands.
Then Bósi asked Herrauðr to sail home to Gautland, but (and) he declared-of-himself to have business in Bjarmaland.

Herrauðr segist eigi við hann skilja, - "eða hvat er í erendum þínum þangat?"
Herrauðr says-of-himself not to (ie that he would not) part with him, “so what is (it) in your business thither?”

Hann segir þat mundu síðar sýnast. 
He says that would later show-itself (ie be revealed).

Smiðr bauð at bíða þeira fimm nætr. 
Smiðr offered (bjóða) to wait for them for five nights.

Bósi sagði, at þeim mundi þat vel duga, ok fóru þeir nú á bátnum til lands tveir saman ok földu bátinn í leyni nokkuru, en þeir gengu til byggða, 
Bósi said, that that would well suffice them, and they journeyed now in the-boat to land, two together, and hooded (ie covered, concealed, falda) the-boat in a certain hiding-place, but (and) they went (on foot) to (the) abode,

þar sem karl bjó ok kerling. 
there where (an/the) old-man lived and (an/the) old-woman.

Þau áttu dóttur væna. 
They had a beautiful daughter.

Þar var vel við þeim tekit ok gefit gott vín at drekka um kveldit.
There (it) was taken well with them (ie they were received well there) and good wine (was) given to drink during the-evening.

Bögu-Bósi leit hýrliga til bóndadóttur, en hún var mjök tileygð til hans á móti. 
Bögu-Bósi looked cheerily at the-farmer’s-daughter, but (and) she was very squint-eyed (CV) towards him in return.

Litlu síðar fóru menn til svefns. 
A little later folk went to sleep.

Bósi kom til sængr bóndadóttur. 
Bósi came to (the) bed of (the) farmer’s-daughter.

Hún spyrr, hvat hann vill. 
She asks, what he wants.

Hann bað hana hólka stúfa sinn. 
He asked her to “entube” (wrap her tube around)(presumably verb from same root as hólkr, noun) his stump (stub, short shaft, stúfi, wk masc equivalent of stúfr, stúfa?).

Hún spyrr, hvar hólkrinn væri. 
She asks, where the tube (ring, hólkr) was.

Hann spurði, hvárt hún hefði engan. 
He asked, whether she had none.

Hún sagðist engan hafa, þann sem honum væri hæfiligr.
She said-of-herself to have none, that which would-be suitable (ie would fit) for it (ie his stump, masc).

"Ek get rýmt hann, þó at þröngr sé," sagði hann.
“I am-able to (geta + pp) widen it (ie the tube) (make it more roomy), even though it should-be narrow (tight),” said he.

"Hvar er stúfinn þinn?" sagði hún. 
“Where is your stump (stúfi)?” said she.

"Ek get nærri, hvat ek má ætla hólkborunni minni."
“I get (learn, geta, Z4) nearer (the truth, nærri-nær, Z5), what I may expect for the-tube-hole of mine.” (I am starting to twig as to what is in store for my tube-hole)

Hann bað hana taka á millum fóta sér. 
He bade her to touch (taka, Z3) between his legs.

Hún kippti at sér hendinni ok bað ófagnað eiga stúfa hans.
She quickly-drew- (back) her hand towards herself, and asked (him) to keep his unwelcome (“unwelcomed, the negative counterpart to the participle <fagnaðr> used adjectivally” – to quote Brian 😊) stump.

"Hverju þykkir þér þetta líkt?" sagði hann.
“Like what seems this to you?” he said.

"Pundaraskafti föður míns ok sé brotin aftan af því kringlan."
“(Like) a shaft-from-my father’s steelyard (pundari+skapt, dative) and the-ring would-be broken from behind from that.

"Tilfyndin ertu, " sagði Bögu-Bósi; hann dró gull af hendi sér ok gaf henni. 
“You-are fault-finding,” said Bögu-Bósi; he drew a gold (ring) from his arm and gave (it) her.

Hún spyrr, hvat hann vill á móti hafa.
She asks, what he wants to have in return.

"Ek vil sponsa traus þína," sagði hann.
“I want to bung (plug, presumably verb from the same root as sponz, noun CV = bung) your hole (I could not find traus anywhere but context suggests it means some kind of hole),” said he.

"Ekki veit ek, hvernig þat er," segir hún.
“I know not, how (what way) that is,” says she.

"Ligg þú sem breiðast," kvað han.
“Lie-you (with legs spread) as-wide-as-possible,” declared he.

Hún gerði sem hann bað. 
She did as he asked.

Hann ferr nú á millum fótanna á henni ok leggr síðan neðan í kviðinn á henni, svá at allt gekk upp undir bring- spölu.
He ventures between the-legs of her and after-that places (the stump) from below into the-womb of her, so that (it) completely went up under the-‘breast-rails’ (lower part of the chest).