My background is a non-dog owner; I will soon be looking after my sister's two year old male goldendoodle who was homed with them at the age of eight months. I'll be looking after him for about a week while his family are out of the country. My nephews will be around if I have questions while my sister is away, and my SO loves dogs1 so I'm not taking this on completely alone!
I will be discussing this with my sister, naturally, but are there any general things I should be aware of? Particularly aspects that someone who is used to having dogs might overlook when briefing someone who isn't! I already know about his usual walk frequency and timing, and that he will be my best friend if I keep some treat on me!
Lastly, I understand that this cross can be prone to anxiety. I've met him and played with him on a few occasions, so I won't be a completely new and strange face. I also assume that I'll be able to borrow his usual sleeping basket and some of his toys while he is a guest at mine; and plan to ask my nephew round so that he has another familiar face. What signs of anxiety should I look out for; and if he does seem anxious, what can I do to ameliorate this?
The week has been and gone without incident. The only things I can think of to add to the excellent answer provided by Victoria are:
Gear for walking. You might think "I walk places, no big deal", but bear in mind you might be walking two or more hours per day and plan accordingly. That means both waterproofs and decent footwear at least!
Knowing a bit about how a particular dog will communicate is useful too. Spending time with him/her (as mentioned in comments) can help here, but if nothing else it can be reassuring to know that what appears to be an "Oh god I'm dying"-type whine might only be a way of saying "I'd like to go out" or "I'm bored and would like attention".
We both had a great week- thanks in part to the constructive advice here! :)
1 She has a very cute looking pitbull back home, unfortunately a continent away so out of the question for the purposes of experience or socialisation with my sister's dog!