Whilst it is possible to add . to your $PATH variable, it is highly recommended NOT to do that. If you walk around to some random place in the filesystem and type something that you think will run a program (vi, emacs, ls, ps, etc), a file in the local directory will become a candidate to run. If you are unlucky, that's NOT the program you wanted to run at all - and if you are running as root, it's even worse, because someone may well add a local file ls that does something completely different than real ls (along with doing real ls, of course - otherwise it would be obvious that it's not real ls, and the user would start investigating the situation). [1]
Instead, you should add an absolute path to where you have your executable files, e.g. /projects/mycurrentprojects/bin - or "relative to home", e.g. ~/bin - if you want the path to work in ALL circumstances it's better to use home\mats\bin [obviously using the right username for yourself]. That way, only files in a certan set of directories are applicable, and no matter where you are, only programs that are in those specific directories are chosen as "possible candidates to run".
[1] Yes, I realize that the search order and various other factors will also matter here. But it's generally not a great idea to add "current directory", no matter what objections.