ddgonzal has taken the words from my mouth. Do it by the book. It's probably overkill, but i like to rotate the crank at least once each time that i add something.IE Install crank in block, rotate it. Install rod & piston, rotate it, & so on for every single item. That way you get a feel for how it's going together. If there is a problem, you will pick it up straight away.

I also like to pre lube the engine prior to startup. In this case, leave the plugs out & spin the engine on the starter untill you have oil pressure. [Fill the filter before installing it to save the battery] This way you should have oil pressure right on startup. It seems a simple enough thing to do, but i have seen many who have sweated while their new engine sat at 1500rpm, waiting for oil pressure. If you are running the stock mechanical fuel pump, then this pre lube thing will allow the carb to fill so that first fire up should be painless.

If using the original oil pump, you probably should have pulled it down for inspection. I like to reassemble them with some light grease to help seal the moving parts. This helps to pull up the oil when you first crank it over. Pre oiling it works the same, but these pumps go on horizontally & some of the oil runs out when installing it & makes a mess. Bummer.

Break it in before running it in, watch the temp a lot, be proud of yourself & enjoy every minute of it.
Chris