The sill plate (also known as the "sill" or "mud sill") is comprised of lengths of dimensional lumber laid directly on top of the foundation wall, and is the first part of the frame you'll put down. Position one of the matching sets of the boards you cut for the perimeter of the floor horizontally (flat) over the foundation, making sure the outer edge is flush with the exterior of the concrete. Residential building codes typically specify slightly wider lumber for the sill platetypically either 2in (5.1cm) x 6in (15cm) or 2in (5.1cm) x 2in (5.1cm) boards. Because the sill plate will be in direct contact with the concrete foundation, it's recommended that you go with pressure-treated wood. Use a hammer drill to open holes in the foundation large enough to accommodate the anchors. Insert the anchors into the holes, then lower the boards for the sill plate down over the top. Slip a washer and nut on each anchor and use an adjustable wrench to tighten them down until they're secure. Space your anchor bolts roughly 4 feet (1.2m) apart along the foundation to ensure the sill plate boards are stable. Make sure there's an anchor at least 5 anchor-widths from any unsupported edge, and always leave a minimum of 10 anchor-widths between any 2 anchors. Stand each of the remaining perimeter boards upright on top of the sill plate so that they're flush with the outer edge. Then, drive framing nails down through the lower part of the boards into the sill plate at roughly a 30-degree angle to secure them. The rim joist sits vertically on top of the sill plate along the outside of the frame to create a lip for the main floor joists. You'll use the same size lumber to assemble the rim joists as you will for the main floor joists. For most jobs, 2in (5.1cm) x 10in (25cm) boards are an ideal size. If you like, you can also use metal braces make sure the connection between the sill plate and band joist is extra secure. Screw the braces into the wood at one end and the foundation at the other to clamp the 2 materials together. Floor joists should be spaced no more than 16 inches (41cm) apart from center-to-center to provide adequate stability. Use a tape measure to measure 16 inches (41cm) in from the edge of the rim joist and draw a small notch. Make another notch every 16 inches (41cm) to confirm the distance between each next joist. The length of your joists will vary depending on the size of the room and the exact materials you're using. Be sure to consult your local building codes before marking the position of your joists. They may specify different spacings to suit different building materials. Set each of the boards you cut for the main floor joists in place along the lip of the sill plate, making sure they're properly aligned with the markings you made. When measured, cut, and placed correctly, the main floor joists should fit flush against the rim joists. Fasten them to both the sill plate and the rim joist by driving framing nails through the outer edge of the frame. Use 2-3 nails for each joist and drive them at a slight downward angle to make sure boards don't budge. Joist hangers can help you work more quickly and efficiently if you're installing multiple joists at once. Simply fit a hanger over each of the spacing marks you drew, nail them to the rim joist, and slide the end of the joist down into the slot. Bridging involves placing short sections of material perpendicularly between the joists to stabilize them. To install standard metal bridging, brace the pointed ends of the bars against the joists, then nail down the open ends. Install bridging on either end of the joists at a distance of of their total span. If your floors are 15 feet (4.6m) long, for example, you would position a brace 5 feet (1.5m) from either end. Alternatively, you can fashion your own block supports by cutting 4in (10cm) x 4in (10cm) boards into 16in (41cm) sections to fit in between the joists. Line the blocks up in a row perpendicularly with the joists, then nail them into place through the face of the next joist. Bridging cuts down on the flexion of the lumber, reducing the stress put on it and extending its lifespan. Lay down 34in (1.9cm) tongue-and-groove plywood panels over the joists, then use wood glue or panel adhesive and galvanized flooring nails to secure each panel around its edges. Work in small sections until the entire floor is covered. When you're done, your floor will be framed and ready for the next phase of construction. Apply the glue a single section at a time. You don't want it to dry out before you have the chance to lay down the subfloor. Using both nails and glue (instead of just one or the other) will help ensure a perfectly flat, stable surface and prevent squeaking underfoot.
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One-sentence summary -- Put the sill plate in place. Fasten the sill plate to the concrete foundation with anchor bolts. Set and fasten the rim joists. Mark the position of each floor joist along the sill plate. Set the floor joists. Add bridging between the joists if they're longer than 9 feet (2.7m). Install the subfloor.

If the air outside of your home is drier than the air inside, open all as many windows and doors as you can to help the air circulate. You should be able to feel whether the air is drier just by stepping outside, but if you're not sure, you can purchase a humidity gauge from a hardware store. If it's sunny outside, it's probably less humid outside than it is in the home. However, you'll likely need to shut the windows and doors at night, when humidity outside increases. Help your home dry faster by opening up damp closets and cabinets. This will allow the air to circulate more freely and will help lower the overall humidity in the home. Sometimes drawers will swell and will be difficult to remove. If this happens, don't try to force them just open the cabinet beneath the drawer. You need air to circulate through your crawl space in order to dry underneath your wood floors. If your crawl space is flooded, use pumps to remove all of the water. You may also want to place a fan in the crawlspace to circulate the air. If your ducts flooded, they'll be full of dirt and silt which may contain contaminants which are dangerous if you breathe them in. Clean the ducts yourself or hire a professional for a duct cleaning before you turn on your central air unit again. You can use dehumidifiers and window air conditioners to reduce the humidity in the air, especially in closed-in areas. You can use a personal dehumidifier, but for severe flooding, you might have better results by renting commercial dehumidifiers, which remove 3-4 times more water than home models. For best results, close nearby windows and doors when you're using a dehumidifier. Desiccants are materials which are used to absorb moisture. They're especially useful when you place them in closets or other areas where air doesn't circulate, and they can be purchased at hardware, grocery, or drug stores. Examples of desiccants include clay-based cat litter, calcium chloride pellets, and chemical dehumidifier packs used to dry boats.
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One-sentence summary --
Open the windows and doors if the humidity is lower outside. Open closets and cabinets and remove sliding drawers. Pump out the crawl space if you have one and it flooded. Avoid using the central air conditioning if your ducts were under water. Run dehumidifiers if the water has seeped into the wood. Use desiccants to remove moisture from closed-in areas.