The fasting we do is so complex and should be set up with a spiritual father for each individual. After 8 years in the Orthodox church I can almost say I have made it to the serious fasting. But when I began I was very cautious, as all newcomers should be.
We fast from all animal products for the most part.
link which explains our fasting.
Here is the explanation of our seasonal schedule of fasting. It is really overwhelming for most newcomers to the church and can be hard to follow.
"Some of the fasts of the Orthodox Church are for one day, some for many days. Among the single-day fasts are included Wednesday and Friday throughout the whole year with the exception of fast-free weeks and the days between Nativity and Theophany; the eve of the Baptism of Christ (eve of the Feast of Theophany, January 5); and feasts that are held as fast days - the Beheading of John the Baptist (August 29) and the Exaltation of the Cross of the Lord (September 14). There are four fasts a year which extend for many days. On the Monday after Cheesefare week begins the first fast of the Spring- it is called Great Lent due to its special importance, and consists of the fast of the Holy 40 Days in imitation of the 40-day fast of the Lord in the desert and the fast of Passion Week, dedicated to the commemoration of the saving sufferings of Christ. A week after the Sunday of the Holy Trinity (Pentecost), the Apostles' Fast begins and this extends to the day of the Holy Apostles Peter and Paul (June 29). The faithful use the Dormition Fast (from August 1 to 14) to prepare for the celebration of the Dormition of the Theotokos. The Nativity or St. Philip's Fast extends for 40 days from November 15 through December 24. According to the Church Typicon, during Great Lent and the Dormition Fast only vegetable products are allowed to be eaten, [Tr. note: except during Great Lent on the Feasts of Annunciation and Palm Sunday, and during the Dormition Fast on the Feast of the Transfiguration] whereas during the Apostle's Fast and Nativity Fast fish is allowed."
On exceptionally holy days I try to fast by eating only one small meal a day. I have done this a few times and truly found it to be blissful. Once I went 24 hours with nothing except communion, and simultaneously attended several services. On Holy Saturday I usually go without anything but a glass of wine. It seems to only be a greatly rewarding task when I am able to be in church most of the time.
LOL, the dang everyday world really gets in the way of spiritual practise. :-)