How on earth Kerbal do you get solid rocket stages big enough to get you up to orbit alt before switching to the liquid rockets?
Ok, that's one problem there already: Solid rocket boosters are horribly inefficient. They provide a lot of thrust in a short period of time so they're decent for getting off the ground, but getting
all the way to orbit on nothing but them is going to be a pain unless you really
really know all the quirks of the physics engine... Or use like 4 stages of ridiculous numbers of them I guess.
For getting started, here's what I suggest: (Begin: DRAGNAR'S GUIDE TO GETTING A ROCKET TO ORBIT IN LIKE THE SLOPPIEST WAY EVER.)
1. Start with a core of a capsule, some science instruments, and a small fuel tank+engine on the end of that. (The stumpy little one with 390 ISP in vacuum. Can't recall it's name, but there's not many engines to check!)
2. After a decoupler from what you built in step 1, add two of the tallest liquid fuel tanks you have, and stick the most powerful engine you have on the bottom of that.
3. At this point, you've got a tall thin rocket in two stages. Next, slap on some radial decouplers and solid rocket boosters around that second stage. You should be able to get some basic radial ones with just near-kerbin science, but they can probably be done without anyway. This stage won't reach orbit. Heck, an SRB with
nothing attached won't reach orbit, so one stage of them can't do it no matter what you do.
That three stage rocket will almost certainly get to orbit. Heck I usually use a somewhat modified version of that basic setup (replacing the SRBs with an asparagus) for early mun/minmus science trips. But you'll need to do it right - you can't just burn straight up, then turn the rocket over once you've reached 70k. Instead, you slowly start tilting the rocket east at 10k - try for being at about a 45 degree angle once you've hit 40k. Once the map says your max height has reached 80k or so, stop burning til you're closer to that height - then point prograde and throttle up til you're in orbit.