This thread has suddenly gotten very popular, so I'm editing it to reiterate that these commands are in Scottish Gaelic, just so that no one is misled. Here's a a link to the set of dog commands in Irish Gaelic on this site, for those who were actually looking for that:
http://www.irishlanguageforum.com/viewtopic.php?f=28&t=606&p=4737#p4737 I'm also editing the subject heading to make the thread easier to search for.
These commands were collected from a number of online lists in various places, which I've corrected as needed and supplemented by ones which I found in my dictionaries, since no comprehensive online lists were found.
I've placed the word "Bi" in brackets wherever it occurs as the first word in a command, because it can and probably should be left out. I've read that dogs focus heavily on the first syllable, and that commands should be as short as possible, so having several commands which all start with "Bi' would presumably be confusing (when talking to a dog, being 100% grammatical is not exactly critical).
For my own future use, I created an alphabetical list with the same commands I had for my Irish list of dog commands (more or less), so it may not contain everything you wanted. If you point out any commands which are missing from what you wanted, I can try to add them.
Gaelic Dog Commands - Briathrachan chù ann an Gàidhlig
Attack / Attack [him/her] - Gabh chuige / Gabh [air/oirre]
Attention - Aire
Away - Air falbh / Theirig
Bad dog - Cù dàna
Bite - Bìd
[Be] Careful / Beware - [Bi] Cùramach / [Bi] Faiceallach
Come - Trobhad
Come here - Thig anseo
Come with me - Thig leam
Come in - Thig a-steach / A-steach leat
Down / Lay down - Sìos / Laigh sìos / Laighe
Drop it - Leag sìos e
Fetch [it / that] - Faigh [é / sin]
Give it to me - Thoir dom é
Go home - Theirig dhachaigh
Good boy - Buachaille
Good dog - Cù math
Good job - Math thù fhèin
Heel / Come to [my] heel - Sàil / Gu sàil / Thig air mo chùl
Here - An seo
Here you are (when giving food) - Seo dhut
Jump - Leum
Leave it / Let it go - Sguir dheth
Left [hand] [on/to the left] / On my left - Air [làimh] chlì / Air mu làimh chlì
Look / Look at me - Seall / Seall orm[sa]
Off with you - Tog ort
Play dead - [Bi] Marbh
Quiet - [Bi] Sàmhach
Relax - Gabh fois
Right [hand] [on/to the right] / On my right - Air [làimh] dheis / Air mu làimh dheis
Roll over - Cuir car [air char]
Shake / Give me your paw - Thoir dhomh do spòg / Crath spòg
Seek / Track it - Lorg / Faigh lorg
Show me your paw - Seall dhomh do spòg
Sit / Sit down - Suidh / Suidh sìos
Speak - Labhair
Stand / Get up - Seas / Èirich
Stay / Wait - Fuirich / Fan
Stop - Stad
That’s it - Sin e
There - An sin
Want to go for a walk? - Coisich?