RPM to shift at and how to launch is the 2 things for practicing.
No one can really tell you which is best for either of these because of each car is so different.

In general since your mostly stock, you are probably losing power going all the way to red line. If you really want to know when to shift, you can take it to a dyno and find out when to shift. If you don't want to do that (I personally wouldn't) just try different shift points (probably between 5700 and 7000) down the 1/4 mile and see what you get. Don't just compare the ET time, but also your mph and times at 60' and 1/8.

The launch will depend on temperature, track prep, your tire, your weight, etc. Basically if you spin too much then lower you launch rpm and if you bog then raise it.

Spinning inbetween 1st and 2nd probably means you stepped on the gas too early shifting. Lowering you PSI on your front tire will make a big difference on your launch.

Hope you find that helpful.