We've never made our own, but a local store sells one that is pre cut with a 2 inch hole down the middle, with an intersecting horizontal hole in the bottom. In the hole is a small piece of waxy cardboard....lite it, and you're done.
We had to buy ours because of park regulations and we didn't have a log nor the chainsaw to make our own.
I liked it, with two caveats....
1) the heat doesn't radiate as well as a traditional fire since much of the flame is encased inside the log.
2) the commercial one we used was a softer wood, it smoked a bit (black smoke) and threw a lot of fly ash.
The first is intrinsic to the design. The second was caused by soft wood.
The candle was nice because it started very easy and gave an awesome coal bed when it was finished. It also was near zero maintenance. It burned for several hours taking no additional attention, except to add wood on top when the candle itself was nearly burned up.
What I added was a traditional log cabin style stack which burned hot and strong due to the incredible coal bed.
Our neighbor at our last gathering built an "upside dow " fire.....this worked amazingly well...big stuff on bottom, smaller on top, with kindling and tinder on top of that....lighting the tinder burned down through the stack. I think I liked this method better than my traditional fire or the Swedish log we bought.