Zlib license question

I’m patching/porting some zlib licensed SDL helper libraries. According to the license, you need to plainly mark altered source versions. You’re also supposed to make sure the fork is not confused as the original software. Does anyone have any best practices or suggests on how best to accomplish this and to adhere to the zlib license when modifying the code? Any examples of other code that does that sort of thing or a list of steps to make sure to adhere to would be really helpful. Any information on best practices or any other recommendations on this would be appreciated. Thanks.