Sure.

Buy a CRX. Make sure you have enough money and credits, then fill the tank. Should take about $95 and 5 credits.

Log in about every 8 hours at least to get the most credits (max is 800, you get 15 per 10 minutes, or 800 in 8.9 hours.)

When you work, expect about $3.50 per credit worked.

Any time you work, follow it immediately with doing something "safe." So starting out, buying parts is safe.

What I do, is open "work" in a new window.
Then I calculate how much money and credits I need for a part, and make sure I can work (@$3.50/credit) enough to get the part and install it.
THEN I enter the required amount of credits to work, hit Enter, and immediately switch windows to buying the part, and hit the Buy button.
That way, you won't have your car stolen.

Then just save up and buy parts and have them installed. I wouldn't even worry about sponsors and racing yet.

Early on, you can fool people by having parts they can't tell you have. Get pistons, cams, clutch, flywheel, weight reduction, P&P....any of that stuff people can't tell you have it done. That's if you want to have kindof a sleeper I guess you'd call it. Then get intake, header, exhaust, testpipe, throttle body, ECU, and finally nitrous.
I didn't do it in that order, but I would if I were doing it over.

When you've bought all the parts, it's time to race some unsuspecting victims. But first you have to dyno tune. I did my writeup, but it's really just as simple as adjusting the numbers on the right up and down to move the line on the graph down and up, respectively. (number up, line down.)

After you get over 2.5% RAR, start getting audio sponsors. They're all grouped together, starting with Alpine, and most are able to be gotten for 10 credits or so. After spending 10, 20, 30, and finally 40 to get my first sponsors...I learned to just spend more than I think I'll need the first time.

Pick your opponents wisely. Losses hurt, but not so much that you should avoid anything but a sure-win. Just check their profile, and what I did at first is avoid anyone with big mods, like nitrous and turbos. Which is why I waited to add nitrous; if I'm avoiding them, then people would be avoiding me as well.

If you're looking to challenge, go to Racers Online, and start at the bottom, look for anyone with a Civic, and near your net worth. Net worth is the value of their car, cash, and uninstalled parts. I know I spend most of my money, and don't hoard unused parts...I doubt any others around that level do either. So it's a decent judge of their competition level.

When you get a chance, raise your skill level. It'll affect your R/T and I would assume your skill at driving, and gauging other racers' cars.

BTW, there's a writeup on the forums for the game. That's where I learned most of this.