The word saints in Revelation 5:8 is the same word used in many other sciptures referring to ordinary believers as saints. Again, this verse does nothing to justify praying to the deceased.
God answers in particular the prayers of the righteous. James declares: "The prayer of a righteous man has great power in its effects. Elijah was a man of like nature with ourselves and he prayed fervently that it might not rain, and for three years and six months it did not rain on the earth. Then he prayed again and the heaven gave rain, and the earth brought forth its fruit" (Jas. 5:16–18). Yet those Christians in heaven are more righteous, since they have been made perfect to stand in God’s presence (Heb. 12:22-23), than anyone on earth, meaning their prayers would be even more efficacious.
The Bible directs us to invoke those in heaven and ask them to pray with us. Thus in Psalms 103, we pray, "Bless the Lord, O you his angels, you mighty ones who do his word, hearkening to the voice of his word! Bless the Lord, all his hosts, his ministers that do his will!" (Ps. 103:20-21). And in Psalms 148 we pray, "Praise the Lord! Praise the Lord from the heavens, praise him in the heights! Praise him, all his angels, praise him, all his host!" (Ps. 148:1-2).
Not only do those in heaven pray with us, they also pray for us. In the book of Revelation, we read: "[An] angel came and stood at the altar [in heaven] with a golden censer; and he was given much incense to mingle with the prayers of all the saints upon the golden altar before the throne; and the smoke of the incense rose with the prayers of the saints from the hand of the angel before God" (Rev. 8:3-4).
And those in heaven who offer to God our prayers aren’t just angels, but humans as well. John sees that "the twenty-four elders [the leaders of the people of God in heaven] fell down before the Lamb, each holding a harp, and with golden bowls full of incense, which are the prayers of the saints" (Rev. 5:8). The simple fact is, as this passage shows: The saints in heaven offer to God the prayers of the saints on earth.