For a tutorial on how to establish the Jewish calendar, see the video linked below - or a PowerPoint with the same information for 5786 at https://docs.google.com/presentation/d/1i2PCfHDp7nfYAd_Sc2z9dYJCmw53zMYX/edit?usp=sharing&ouid=108360675515039678488&rtpof=true&sd=true
For a set of useful apps for the Jewish calendar, download the folder at https://drive.google.com/file/d/1pSUqqwtey05UXUaS2oDp9taegRYQkxgQ/view?usp=sharing.
To use it, download the zip folder, check for viruses, and unzip.
Along with supporting files, the folder contains two html pages. (They only work once the folder is unzipped.)
The two html pages are tools to aid the presentation below.
The first is Calculator.htm, for calculating the molad.
The second is Keviyus.htm, which is a web page equivalent of the 14 keviyuyos chart in the Tur Orach Chaim 428. It shows every detail of the 14 different Jewish calendars, along with some convenient aids to visualization.
There is also a Four Gates folder (ארבעה שערים), which has an interesting html page FourGates.htm that demonstrates the ארבעה שערים in a unique way.
The main presentation is This year's calendar https://drive.google.com/file/d/1OSAmcRssaxU4S-sA2LQiFajNlQLWsz54/view?usp=sharing. It walks through the process of creating a calendar in detail, from beginning to end. The youtube video for that presentation is at https://www.youtube.com/watch?v=rjVnVx1Nbl4. It is for the year 5786.
Another place to get these files: https://github.com/MichoelR/Keviyus?tab=readme-ov-file