My mother calls me "Fiscally Retentive"
1. Ride all the time. It keeps you out of the stores, off the internet, and out of the magazines where all the marketing money is spent to get you to buy. If you ride a ton (and skip a dessert or beer once in a while), you lose more weight on your body than you would be able to lose on the bike by buying light parts. If you ride a bunch, you will find that you are passing many of the folks on the expensive machinery. After all, it is not the machine, but the motor.
2. Pay no attention to what anyone else says or thinks about you or your bike.
3. Wrench your own stuff. You might as well know how in case you are on a trail and your forgot your mechanic. I'd love to stop and help, but I have to get home to dinner.
4. If it ain't broke, don't fix it. Buy good stuff and ride it 'til it breaks. Don't upgrade for the sake of upgrading. I get several thousand miles off road each year, but the newest of my two bikes is a 1998. I have a favorite seat that has a big tear in the middle and the leather is coming off both sides, but it is not dead yet. I also ride tires until they are practically bald.
5. Patch tubes until they won't fit into the tire anymore (just kidding - I usually have no more than 6 patches on a tube before the stem shears off). I buy extra patches for 12 cents apiece until all of the glue is gone in my patch kit. I just pile punctured tubes up in the garage until I get several and then fix them all at once. Usually fix 6-10 tubes in 1/2 hour and never had a patch fail. Once the stems are sheared off or the tubes are shot, buy in bulk (10 for $17).