Often, one wants to flatten beta strands (a.k.a. sheets) so they lay flat like a sheet of paper. Below are several users' approaches:
Rav3n_pl: When we have many sheets in structure and "denovo" is possible do the following:
1. Save structure
2. Write down, sketch on paper or somehow note how sheets need to be connected. You may also wish to make bands to the necessry connections but disable them.
3. Using the Design Mode, change the structure of the entire protein to all-sheets.
4. Use the Tweak tool to make one long, straight sheet.
5. Restore the original structure.
6. Freeze the sheets.
7. Enable those bands you set in the beginning.
8. Wiggle on low Clashing Importance. Experiment with various values for (CI).
9. Now, crying silently... ;]
Kimo: One way to flatten a sheet is to place bands at both ends and pull it flat. This often works better if you place the bands and then rebuild. Remember, when trying to flatten a sheet, it has to have room to move. If the adjacent sheets or segments are to close a clash will develop and the tweak will not happen.
This technique may need this recipe http://fold.it/portal/recipe/29188 to set band strength. Options for settings within the recipe can be located at the top.
Rav: Now we can put 1 band between the ends of a sheet and make it 4x longer than the segments in the sheet, and then wiggle or rebuild to stretch it. IMO wiggle most of time works better than a rebuild.
Tutorial see also > related to flattening sheets paper
More Techniques at > The Foldit Labs