Ok me and my gf really want to make love were both old enough and both really want to.. advice?

Hay, I just turned 19 and me and my girlfriend want to make love I REALLY WANT to make it really good for her its both our first time and we know we are perfect for each other... p.s im proposing to her at christmas lol... we were planning to wait for marriage but we have been getting so intimate its become way to hard to resist... Ive licked her and touched her but she never even masturbated so shes to tight for me to actually put anything inside her even though she really enjoys it we attempted once before and I wouldnt... fit.... since then I bought lube and weve decided that will help alot but shes scared its going to hurt alot... i have an idea and i want to know if it will help...If I use lubricant and start to finger her over a period of time will that help for our next attempt?.. any other advice is usefull and appreciated...