Is your clutch pedal adjusted correctly?
Do you feel pressure in the clutch pedal?
Do you have any other problems with any gears besides 1st?
When was the last time you checked/replaced the trans fluid?
Having difficulty shifting into 1st gear may not be the clutch, you could be low on trans fluid or it may be time to swap out that old fluid for some redline.
Bleeding the clutch is pretty simple, when I do it I make sure the clutch master cylinder is topped off and I attach a line from the slave cylinder bleeder valve and run it into a clear container filled with brake fluid. Have someone pump the clutch and then press it and hold it to the floor, open the valve to let all the air bubbles out (You'll be able to see it through the container, hence why it has to be clear). Do this until the air bubbles stop. Don't forget to keep checking/filling the master cylinder, if it gets too low it will suck up air and you'll have to do it all over again. Dot3 and above brake fluid is recommmended.
Trans. fluid is easily drained by a 24mm bolt (I think I used a 15/16 socket) on the passenger side. Depending on where/how high the car is jacked up, you may need to lower it to help get all that fluid out. The fill bolt is the same size on the driver's side, although it's easier to fill through the shifter hole. Remove the center console piece around the shifter, the 4 bolts, and then pull up the shifter cover, then remove the 4 more bolts. All 8 bolts are 10mm. Then the shifter pulls right out, use a funnel and iirc it's 3 liters (3.2 quarts) to fill it. To be sure of the level you can remove the fill bolt and fill the transmission until the fluid starts to come out of the fill hole.
