For questions regarding the changepage package that provides commands to change the page layout in the middle of a document, and to robustly check for typesetting on odd or even pages.
The changepage package provides commands to
1. robustly detect odd or even pages
To determine if TEX is typesetting on an odd or even numbered page, the \checkoddpage command can be used anywhere in the body of a document. \ifoddpage is either set to <true> or <false> if on an odd or even page, respectively.
2. locally adjust the margins
With the help of the adjustwidth environment (and its starred variant for twosided documents) the left and right (inner and outer) margins can be locally changed. See also the adjustwidth tag.
\begin{adjustwidth}{<change to left margin>}{<change to right margin>}
3. change the textblock
With the help of the \changetext command, the size and horizontal position of the text block on a page can be changed. The lengths are added to the corresponding current lengths and the new layout remains in effect until another \change.... command is issued.
\changetext{<text height>}{<text width>}{<even-side margin>}{<odd-side margin>}{<column sep.>}
4. change the entire page design
The \changepage command cn be used for changing the general layout of a page. The given lengths are also added to the corresponding current lengths and the new layout remains in effect until another \change.... command is issued.
\changepage{<text height>}{<text width>}{<even-side margin>}{<odd-side margin>}{<column sep.>}{<topmargin>}{<headheight>}{<headsep>}{<footskip>}
