First, I suggest starting with winter-themes if that makes you more comfortable. Snowmen, snowflakes, the penguin, and the like are usually a good place to start (later, you might do the Santa, the cross, angels, and the religious or Christmas specific things as you become more comfortable). You still exchange gifts, you still use wrapping paper--but, until you are comfortable, you use the winter themes rather than the Christmas specific themes. Clear LED or warm-white LED lights add to the winter theme nicely.
On the other hand, you might just decide to jump in with both feet and go the whole nine yards. I would then recommend a web site www.allthingschristmas.com for some ideas (you do not have to buy anything from them--just browse for ideas). You can decide then whether you want a mostly winter theme, a mostly secular Christmas, or a mostly religious theme--or a combination of all of the above.
Another scripture I suggest reading in context (out of your own Bible, preferably not the Not Well Translated), is Luke chapter 2. Focus on verses 10-14. It appears that the angels were putting on quite a celebration of Jesus' birth--the first Noel, actually. Do you know of any scriptures that show how those angels were made into demons like the ones that materialized before the Flood? If not, then what's scripturally wrong with celebrating Christmas? Nothing.
Thanksgiving is another matter. Here is a day set aside for giving thanks for the "blessings" you received, and the witlesses have the nerve to ban it. I see nothing wrong with that. If you prefer a more secular theme, you might just use this day to enjoy to the full the fruitage of your labor. Now, where in the Bible does it say that it is wrong to do that?
