Usually, the sleeve has a break in it that will be visible. Very gently squeeze the sides of the sleeve together until that break is almost connected. That should get you to the right point. You will need to do this for all four wires.
If you have the opposite problem, find a round pointed tool like an awl or a round toothpick. Grab the sleeve with your pliers in the middle of the sleeve. Do not grab it by the back flat portion! Now with your other hand, gently press the round tool or toothpick into the sleeve so it expands ever so slightly at the end. This will be good enough as the rest will expand as you slide it on.
We prefer to slide the sleeves on from the top to give us more room, you should be able to successfully do this now for all four following the color code or diagram you made and color code. Just be gentle as you slide the sleeves on. We can not tell you how many times we have broken those little tabs ourselves by going too fast or putting too much pressure and something slips or gives. Take your time.
Rough Balance & Alignment
After you are done with this step, do a rough balance of your turntable tracking force, but do not apply any anti-skate. Your turntable manual should walk you through these steps, but we also have a large variety of setup videos on how to do this for the majority of the turntables Audio Advice carries.
It is now time to align your cartridge. Some Rega turntables and cartridges make this really simple as the headshell and cartridge have 3 screws instead of the normal 2 and it self aligns. For everything else, we will dive in now.
For this step, it is best if you are looking down on your turntable and able to get at eye level with the tonearm. Hopefully, you still have the alignment gauge that came with your turntable originally. If not, you might be able to print one out online from your turntable manufacturer, then very carefully punch out a hole the size of your turntable spindle. You can also purchase cartridge alignment tools, including the MoFi Geo-Disc, Ortofon alignment tool, Pro-Ject Align It DS2, and the Pro-Ject Align It.