Building a wall

simple garden wall

I measure the lengh, dry lay, if it ends needing half a brick, how best to do that, or maybe make sure it ends take a full brick

If you end on a full brick, then the next one up will be a half brick anyway (slightly different if you use something other than stretcher bond, but you get my drift: by definition, it can't always end with a full brick).

If its long, then there is a good chance you could loose the half by adjusting the joints

But for reference, all walls in stretcher bond end in a half brick (or header return) on alternate courses

Each course should end with the same face - ie a stretcher or a header. If not possible then "reverse bond" and have the ends finish in opposite faces ie stretcher and header.

the only thing to add to the above comments is, if you are having more than on manufacturer of brick, be prepared for small differences in length.
this may occur if you use an engineering brick at ground level and a softer or differing brick above.

although they will vary very little, a tight perp on one type of brick may be impossible on another or subsequent courses, if the subsequent brick happens to be slightly bigger.

the moral of the story is - watch your perps!