Depends on how much room you have. If you are shooting color, just bring an extra box. If you are shooting BW and developing yourself, you will need at least three boxes or bags within a big box: -, +, and N. OR...

What I have started doing is keepinig all negs of all different exposures together in one separate box, and I list on a piece of paper each negative that goes in the box, from the bottom up. It takes a little longer because I double check holder order to the order of the exposed film in the box, but so far it has worked. I simply figured out a little routine:

1) Every time I load film I put a little removable label on each side of the holder. On the right of the label is a big label with the kind of film: H for HP5, F for FP4, B for Bergger, etc.

2) Then there's about 3/4 inch of space. On it I write a two word description of the scene and what the development should be.

3) When I outload the holder, I make sure I transfer the label order to the sheet bottom first, then the sheets out of the holders and into the box, and I'm done.

4) When developing, I do N's first, then minuses, then pluses. I count film sheets in the dark, and take out the ones to be develpoped.

Sounds more complicated than it is, and it allows me to travel with just a few holders, two boxes, and a tent.