Reciting the brocha on the candles:
Meals on Erev Shabbos:
We may eat and drink until Shabbos begins. Once Shabbos has began we are obligated to make Kiddish before eating.
Our Sages forbid eating lavish meals Erev Shabbos. The reason is because we want to show honor to Shabbos and therefore enter with an appetite, we eat larger meals on Shabbos and also the Sages were worried someone might be too engrossed into their eating and will not be able to prepare accordingly for Shabbos.
We may partake in a Seudas Mitzva on Erev Shabbos. Its best to have such a meal in the morning.
Adding to Shabbos:
Its is a Mitzva to add onto Shabbos. The custom is to accept Shabbos slightly earlier on a Friday and wait a little later on Moztei Shabbos before concluding Shabbos.
The amount of time needed for this "addition to Shabbos" is not given in the Gemora. The general custom is 20 mins before sunset to accept Shabbos.
One should state verbally that they are accepting this addition to Shabbos by saying, "I hereby accept tosefes Shabbos."
Haircuts on Erev Shabbos:
If a person's hair is long, it is a mitzva for him to cut it before Shabbos. It is best to have the haircut on Friday to show it is in honor of Shabbos.
Cutting Nails on Erev Shabbos:
It is a Mitzva to cut nails every Erev Shabbos in onor of Shabbos. The rema rites that one should not cut their nails in order. One should start with the 4th finger of the left hand and then to the second finger, then the 5th, 3rd and 1st. On the right hand the order is: 2nd,4th,1st,3rd,5th.
Other Poskim rule that there is no problem with cutting the nails in order. The Mishna Brurah holds its best to follow the rema's ruling.
Finger nails should not be cut on Thursday as it will then appear the nails weren't cut in honor of Shabbos as they would have started to grow already.
Some opinions hold that one should not cut their finger nails and toe nails on the same day.
Rav Yehuda HaChossid brings down, one should not cut their hair and nails on Rosh Chodesh even when it falls on Erev Shabbos.
Bathing for Shabbos:
One must enter Shabbos clean and in a state of purity. One has an obligation to use hot water while bathing. Using cold water does not fulfill ones obligation.
One must dress in special clothes set aside for Shabbos. This brings honor to Shabbos. It is also a custom to wear the clothes until after Havdola has been said on Motzei Shabbos.
*Note: Some have a custom to wear Shabbos clothes until 1 hour after Shabbos.
Preparing for Shabbos:
On all foods and drinks one recites the after brocha of "borei nefashot", with the following exceptions: bread(which we recite birkat hamazon/grace after meals), the seven species(wheat,barley,grapes,figs,pomegranates,olives and dates which on these we recite the after brocha of mein shalosh, the same applies to wine)
If there is produce from the ground and produce of the tree before one and they recited the brocha on the produce on the ground first, they need to recite the brocha on the fruit as well because the fruit of the tree is not exempted by the brocha on the produce of the ground. If one recited the brocha on the produce of the ground and had the fruit in mind then we can rely on this brocha and no need to say another one on the fruit. The Rabbis instituted a ruling that we should always recite the correct brochas on all foods so we should not exempt any food by reciting a general brocha, in this case we should recite a brocha on the fruit and also the produce of the ground.