The holidays of Passover and Shavuot are even more connected. They are just over seven weeks apart. The Omer is a count of forty-nine 49, seven weeks, 7 X 7 = 49. We begin counting on the second night of Passover.
The count goes for 49 days. The 50th night begins the holiday of Shavuos; Shavuos means "weeks," referring to these 7 weeks of counting. Shavuos is the day G-d gave the Torah, and thus the entire counting period becomes one of continuous elevation and preparation - from the status of an Egyptian slave to one ready to receive the Torah.
The mitzvah is to count both days and weeks. Therefore, on the eighth day, we say, "today is eight days, which are one week and one day in the omer." The Omer may be counted in any language, as long as it is understood by the counter.The Jewish days begin at sundown, and we wait until full dark to count the Omer.
Finally, only eleven years ago I counted the full Omer for the first time. Our son-in-law, who was then working for a cellphone company signed us up for free cellphone reminders. The only remaining challenges were Shabbat and the last day of Passover, when the phone is kept off. Even today, those are my most difficult nights to remember to count.
Since then I've also signed up for email reminders, considering that besides Shabbat and Jewish Holidays I check my mail every day. And for the years I don't get cellphone reminders from a "service," I've set my phone up for reminders all by myself. Use your "appointment book" for a daily sefira reminder.
If you have any other useful and workable and free hints, please comment, thanks.