If you want to customize your Simple:Press theme we recommend you create a separate new theme all your own. You can read how it is done in our Creating a Theme article.
Once you have created your own theme it is a good idea to check it with any new Simple:Press updates and compare any new changes to yours. Doing this allows you to take advantage of new features or fixes.
It is easy to do and you only would need to do it when the Simple:Press theme that you mimicked is updated.
We have created some tips on how this can be done.
In our Creating a Theme article we suggest you copy a supplied theme and then customize from that point. If you keep the theme available in your themes folder anytime there is an update to that theme you will be notified by both WordPress’s update notifier and in Simple:Press’s administration panels.
You can then update to the new theme so you have it available to compare any changes it may have with yours.
It also a good idea to keep the original theme available at all time in case there is ever an error in your custom theme that might make it so you have to take it offline for some time to fix.
If this ever happens having a backup theme is priceless.
The best way to compare your theme’s php file(s) to another is to use a text type comparison program. There are several available for both PC and Mac. These programs allow you to load two different files and show you line by line any difference between the two files. You can then copy or edit any lines from an updated theme to yours.
We have used a few different programs to compare files on a PC. One is Notepad++ and it’s Compare plugin. This is a free source code editor and Notepad replacement that supports several languages.
Another widely used PC program is WinMerge. WinMerge can compare both folders and files, presenting differences in a visual text format that is easy to understand and handle.
WinMerge also gives you the ability to see line by line differences and make quick changes from the original file to your custom one.
Bare Bones Software has a very nice tool named TextWrangler. It works well as a general purpose text editor and comparison program.
This program is also free
Using the program of your choice you would load both files, your theme and the newly updated Simple:Press theme, into the editor.
Using their compare feature you will quickly see and differences highlighted. At that point you can then copy any newly changed items in the Simple:Press theme to yours.
Keep in mind that any changes you have made to your custom theme that you have made that you want to keep will also be shown as different and not all changes to an updated theme may be something you wish to add. Be sure to take a minute and look at each difference before deciding which one to use.