Here‘s my translation. Comments, suggestions, alternate readings highlighted. Queries underlined.

Kveðja

Alan

Gestur svarar þessu einu: "Era sjá draumur minni."
Gestr answers this only: „This dream is not (er + a (negative suffix)) less.“

Enn mælti Guðrún: "Sá er hinn þriðji draumur minn að eg þóttist hafa
Still Guðrún spoke: „That is my third dream that I bethought-myself to have

gullhring á hendi og þóttist eg eiga hringinn og þótti mér bættur skaðinn.
a gold-ring (band) on (my) arm/hand and I bethought-myself to own the-ring and (it) seemed to me (that it) made-up-for (pp. Of boeta, Z2) the-loss.

Kom mér það í hug að eg mundi þessa hrings lengur njóta en hins fyrra. En
(It) came into my mind (ie occurred to me) that I would derive-benefit-from this ring longer than the former. But

eigi þótti mér þessi gripur því betur sama sem gull er dýrra en silfur.
this treasure did not seem to suit me better to that (extent) that gold is more-precious than silver.

Síðan þóttist eg falla og vilja styðja mig með hendinni en gullhringurinn
After-that I bethought-myself to fall and to want to support myself with the-(my)-hand but the gold-ring

mætti (moeta) steini nokkurum og stökk í tvo hluti og þótti mér dreyra úr hlutunum.
met (came into contact with) a certain stone (dative singular)and sprang (split) into two parts and (it) seemed to me to bleed out-of the-parts.

Það þótti mér líkara harmi en skaða er eg þóttist þá bera eftir.
That seemed to me more-likely (comparitive) (closer to?) a grief than a loss (not sure what the distinction is here) which I bethought-myself to bear (endure) after.

Kom mér þá í hug að brestur hafði verið á hringnum og þá er eg hugði að (hyggja) brotunum eftir
(It) came then to my mind that a crack (noun) had been in the-ring and then when I looked at (see hyggja at, Z5) the fragments afterwards

þá þóttist eg sjá fleiri brestina á og þótti mér þó sem heill mundi ef eg
then I bethought-myself to see (the) more cracks in (it) and (it) seemed to me (it) would still (þó) (be) whole (in one piece) if I

hefði betur til gætt og var eigi þessi draumur lengri."
had better taken-care-of (it) and this dream was not longer. (ie that was the end of the dream)“

Gestur svarar: "Ekki fara í þurrð draumarnir."
Gestr answers: „The dreams do not go into decrease (ie wane, see fara i þurð, Z18)

Og enn mælti Guðrún: "Sá var hinn fjórði draumur minn að eg þóttist hafa
And still Guðrún spoke: „That was my fourth dream that I bethought myself to have

hjálm á höfði af gulli og mjög gimsteinum settan. Eg þóttist eiga þá
a helmet on (my) head of gold and much (adv) set with gem-stones. I bethought-myself to own that

gersemi. En það þótti mér helst að að hann var nokkurs til þungur því að eg
treasure. But that seemed to me especially (most of all, helzt) that (ie I noticed especially that), that it (ie the helmet) was somewhat (rather) too heavy (see nökkur, Z1) because I

fékk (fá) varla valdið (valda) og bar eg hallt höfuðið og gaf eg þó hjálminum enga sök á
was barely able to wield (it) (fá + past participle, Z7) and I bore the-(my)-head leaning-on-one-side and (but) I nevertheless gave no cause (gefa enga sök, ie attributed no blame) for (this) to the-helmet

því og ætlaði ekki að lóga honum. En þó steyptist hann af höfði mér og út á
because I intended not to part with it. But nevertheless it tumbled-down off my head and out into

Hvammsfjörð og eftir það vaknaði eg. Eru þér nú sagðir draumarnir allir."
Hvammsfjörðr and after that I awoke. Now to you (dative, indirect object) are said (related) all dreams (nominative, subject).”

Gestur svarar: "Glöggt fæ eg séð hvað draumar þessir eru en mjög mun þér samstaft þykja
Gestr answers: “Clearly I am able to see what these dreams are but much will (it) seem to you all-of-one-burden (a bit tedious?)

því að eg mun næsta einn veg alla ráða. Bændur muntu eiga fjóra
because I will almost(næasta) in (the) one way interpret (raða, verb) all (of them). You will (munt + þú, not subjunctive) have four husbands (bóndi)

og væntir mig þá er þú ert hinum fyrsta gift að það sé þér (dative) ekki
and (it) gives-expectation to me (ie I expect, see vænta, Z3) when you are given-in-marriage to the first (husband) that that would-be for you not

girndaráð. Þar er þú þóttist hafa mikinn fald á höfði og þótti þér illa sama,
a love-match. There where you bethought-yourself to have a great head-dress on (your) head and it seemed to befit you ill,

þar muntu lítið unna honum. Og þar er þú tókst af höfði þér faldinn og
there (ie this means) you will little love him. And there where you took the-head-dress from your head and

kastaðir á vatnið, þar muntu ganga frá honum. Því kalla menn á sæ kastað er
cast (it) into the-lake, there (ie this means) you-will (munt + þú) go (part) from him. For that (reason) men (people, subject) call (it) cast into (the) sea when

maður lætur (láta) eigu (eiga) sína og tekur ekki í mót."
a person gives-up (see láta, Z2) his possession(s) (eiga, noun)and takes nothing in return (see  mót, Z4).