1st off - don't listen to people who tell you tech raiding's not worthwhile - they're oblivious to the truth. I've raided for over 6 months now and only once had someone not accept peace right away. I raid nuclear nations and have never been nuked. Will it happen? perhaps -b ut all the raids I've successfully done more than make up for the one that might fail in the future.
2nd - never use Air or CM attacks during a raid - anyone who tells you too doesn't understand how to raid or the point of it and is probably the guy who gets nuked when he tries to.
3rd - Here's how to raid.
Go to Nation Rankings under "View my Nation" on the left side of your screen
Sort in Ascending order by Nation Strength
Using your mouse, highlight the Alliance Stats icon under the Msg Icon for each ruler until you find someone who either doesn't have one (is in None) or is in an AA you don't recognize.
If they have an AA you don't recognize, check it out. If it has 1 member, you're typically good to go right away. If they have more than 1 (3-15 typically) then you need to do your homework. Check their AA on the Wikia and on the OWF to see if they are protected or have treaties. If they don't, then you're good to go.
Once you have a confirmed target, you want to buy max soldiers and tanks, go to defcon 1, change your gov to Communist, and buy 5 barracks and 5 GC's if possible.
Next, go to your deployment screen and based on their troops and efficiency, deploy your troops to get around 80-90%.
Do 2 Cautious attacks and then offer peace immediately
Rebuy the troops and tanks you lost and wait - if they retaliate, you have to handle it appropriately. If they don't retaliate but don't accept peace, raid them again the next day. If they accept peace, make a note of them and don't raid them again.
Hope that helps